Effect of glycation of albumin on its renal clearance in normal and diabetic rats

International Nuclear Information System (INIS)

Layton, G.J.; Jerums, G.

1988-01-01

Two independent techniques have been used to study the renal clearances of nonenzymatically glycated albumin and nonglycated albumin in normal and streptozotocin-induced diabetic rats, 16 to 24 weeks after the onset of diabetes. In the first technique, serum and urinary endogenous glycated and nonglycated albumin were separated using m-aminophenylboronate affinity chromatography and subsequently quantified by radioimmunoassay. Endogenous glycated albumin was cleared approximately twofold faster than nonglycated albumin in normal and diabetic rats. However, no difference was observed in the glycated albumin/nonglycated albumin clearance ratios (Cga/Calb) in normal and diabetic rats, respectively (2.18 +/- 0.39 vs 1.83 +/- 0.22, P greater than 0.05). The second technique measured the renal clearance of injected 125I-labelled glycated albumin and 125I-labelled albumin. The endogenous results were supported by the finding that 125I-labelled glycated albumin was cleared more rapidly than 125I-labelled albumin in normal (P less than 0.01) and diabetic (P less than 0.05) rats. The Cga/Calb ratio calculated for the radiolabelled albumins was 1.4 and 2.0 in normal and diabetic rats, respectively. This evidence suggests that nonenzymatic glycation of albumin increases its renal clearance to a similar degree in normal and diabetic rats

99mTc-DMSA renal uptake in urological diseases measured from renal tomographic images using single photon emission computed tomography (SPECT)

International Nuclear Information System (INIS)

Oishi, Yukihiko; Tashiro, Kazuya; Kishimoto, Koichi; Wada, Tetsuro; Torii, Shinichiro; Yoshigoe, Fukuo; Machida, Toyohei; Yamada, Hideo; Toyama, Hinako.

1987-01-01

To determine renal function, 99m Tc-DMSA renal uptake was measured from renal tomographic images obtained by single photon emission computed tomography (SPECT). A total of 77 tests was conducted on 73 patients with various diseases in the kidneys and urinary tract to determine renal uptake. The correlation coefficient(r) between total renal volume and total renal uptake was 0.3509 and that between renal volume and uptake of 143 kidneys was 0.5433. In 62 patients whose creatinine clearance could be measured, the correlation coefficient between creatinine clearance and total renal volume was 0.2352, and that between creatinine clearance and total renal uptake was 0.8854, that is, creatinine clearance correlated well with renal uptake. Renal volume and uptake determined in 10 normal male and 10 normal female adults were 220 ml and 26.8 % for the right kidney and 239 ml and 27.6 % for the left kidney for the males and 206 ml and 26.4 % (right) and 237 ml and 27.9 % (left) for the females. This method, which requires no blood or urine collection, is very useful as an individual kidney function test to evaluate individual kidney function and to understand kidney function before and after operation in patients with renal and urinary diseases. (author)

Glomerular filtration in kidney recipients measured by plasma clearance of 169Yb-DTPA

International Nuclear Information System (INIS)

Stribrna, J.; Oppelt, A.; Jirickova, E.; Janata, V.; Kocandrle, V.; Sup, I.; Woller, P.; Franke, W.G.

1986-01-01

Values of 169 Yb-DTPA clearance (C DTPA ) calculated after a single injection were compared in 26 recipients of kidneys with renal clearance of inulin (C in ), polyfructosan S (C pf ) and creatinine (C cr ). In 21 patients the examinations were made simultaneously, in 5 patients C DTPA was measured within a short interval after the examination of renal clearance. The mean C DTPA values did not significantly differ from C cr but were significantly higher (p in and C pf (by 33% on average). Investigation of changes in C DTPA as compared with C in and C pf showed no significant difference in glomerular filtration (GF). This was measured using inulin and polyfructosan. The results showed that the differing molecular weight of inulin and polyfructosan S had no detectable effect on the GF of kidney recipients. The plasma clearance of 169 Yb-DTPA similarly to C cr overestimates the GF measured by inulin and polyfructosan clearance. (author)

THE COMPARATIVE ANALYSIS OF RENAL FUNCTION IN LIVER DISEASES USING COCKCROFT-GAULT FORMULAE AND CREATININE CLEARANCE

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Karem Ravi Teja

2018-01-01

Full Text Available BACKGROUND Kidney dysfunction in liver disease can be due to different aetiologies and can have diverse manifestations. Most of the abnormalities of kidney function in cirrhosis are of functional origin namely, sodium retention, impaired free water excretion and renal vasoconstriction with decrease in renal perfusion and glomerular filtration rate. Renal dysfunction in chronic liver disease usually follows a progressive course- the final phase being Hepatorenal Syndrome (HRS. MATERIALS AND METHODS This study included patients with chronic liver disease being treated as inpatients in the Department of General Medicine, Konaseema Institute of Medical Sciences, Amalapuram. Evidence for chronic liver disease being defined by a compatible clinical profile (signs of liver cell failure or reduced liver span along with biochemical (altered liver function tests, reversal of albuminglobulin ratio or sonographic evidence (altered echotexture of liver or tissue diagnosis (positive liver biopsy for cirrhosis. RESULTS Eighteen percent, i.e. 5 out of the 28 patients with creatinine clearance more than 60 mL/minute by Cockcroft-Gault formula were found to have creatinine clearance values less than 40 mL/minute when done by timed urine collection P value calculated was found to be less than 0.0001, which is statistically significant. CONCLUSION In chronic liver disease, serum creatinine alone is not a reliable marker to assess renal dysfunction. Calculating creatinine clearance by using Cockcroft-Gault formula overestimates renal function in cirrhotics. Creatinine clearance measured by timed urine collections should be done routinely to assess renal reserve in advanced liver disease. Alcoholism appears to have adverse effect on renal function when compared with other aetiologies of cirrhosis.

Use of specific radioimmunoassays to determine the renal clearance rates of estrone and 17. beta. -estradiol during the menstrual cycle. [Tritium tracer techniques

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Wright, K.; Collins, D.C.; Preedy, J.R.K.

1978-11-01

Specific RIAs requiring ether extraction only were established for estrone and 17..beta..-estradiol both in plasma and in urine from the nonpregnant female. These assays were used to measure the renal clearance rates of estrone and of 17..beta..-estradiol in eight ambulatory women in the follicular and in the luteal phases of the menstrual cycle. The mean (+-SE) for the renal clearance rate of estrone was 0.71 +- 0.058 ml/min in the follicular phase and 1.26 +- 0.35 ml/min in the luteal phase. The mean (+-SE) renal clearance rate of 17..beta..-estradiol was 0.44 +- 0.055 ml/min in the follicular phase and 0.29 +- 0.043 ml/min in the luteal phase. There was no significant difference in the renal clearance rates of either estrone or of 17..beta..-estradiol between the follicular and luteal phases of the cycle. The renal clearances of estrone and 17..beta..-estradiol were highly correlated (r = 0.84; P < 0.01). The renal clearance rate of estrone was significantly greater than that of 17..beta..-estradiol in both phases of the cycle (P < 0.01).

Comparison of the endogenous creatinine clearance, the creatinin clearance calculated without urine collection and the isotope clearance

International Nuclear Information System (INIS)

Mohacsi, Gabor; Lang, Jenoe; Csernay, Laszlo; Sonkodi, Sandor; Orvostudomanyi Egyetem, Szeged

1987-01-01

Observations are reported relating to the endogenous creatinine clearance, the Tc-99m-EDTA-complex clearance and the creatinine clearance estimated via a selected mathematical formula, with special regard to the problems of renal insufficiency and the nephrotic syndrome. The activity applied was in the range of 3.7-7.4 MBq. It was observed that measurement of the isotope clearance can also be applied to determine the endogeneous creatinine clearance in otherwise less suitable patients. A reliable result is obtained even if the renal function is restricted, but the accuracy of the method may be reduced in nephrotic syndrome cases. (author) 24 refs

Influence of Pelvicaliceal Anatomy on Stone Clearance After Flexible Ureteroscopy and Holmium Laser Lithotripsy for Large Renal Stones.

Science.gov (United States)

Inoue, Takaaki; Murota, Takashi; Okada, Shinsuke; Hamamoto, Shuzo; Muguruma, Kouei; Kinoshita, Hidefumi; Matsuda, Tadashi

2015-09-01

This study was performed to evaluate the impact of pelvicaliceal anatomy on stone clearance in patients with remnant fragments in the lower pole after flexible ureteroscopy and holmium laser lithotripsy (fURSL) for renal stones >15 mm. This retrospective study included 67 patients with radiopaque residual fragments (>2 mm) in the lower pole after fURSL for large renal stones (>15 mm). The preoperative infundibular length (IL), infundibular width (IW), infundibulopelvic angle (IPA), and caliceal pelvic height (CPH) were measured using intravenous urography. Multivariate analysis was performed to determine whether any of these measurements affected stone clearance. Of the 67 patients, 55 (82.1%) were stone free (SF) 3 months after fURSL. The anatomic factors significantly favorable for an SF status were a short IL, broad IW, wide IPA, and low CPH. On multivariate analysis, the IPA had a significant influence on an SF status after fURSL (p=0.010). An IPA renal stones according to our multivariate analysis. Additional studies are required to further evaluate the characteristics of the pelvicaliceal anatomy influencing stone clearance.

Four hour creatinine clearance is better than plasma creatinine for monitoring renal function in critically ill patients

OpenAIRE

Pickering, John W; Frampton, Christopher M; Walker, Robert J; Shaw, Geoffrey M; Endre, Zolt?n H

2012-01-01

Introduction Acute kidney injury (AKI) diagnosis is based on an increase in plasma creatinine, which is a slowly changing surrogate of decreased glomerular filtration rate. We investigated whether serial creatinine clearance, a direct measure of the glomerular filtration rate, provided more timely and accurate information on renal function than serial plasma creatinine in critically ill patients. Methods Serial plasma creatinine and 4-hour creatinine clearance were measured 12-hourly for 24 h...

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

Radioisotopic measurement of glomerular filtration rate in severe chronic renal failure

International Nuclear Information System (INIS)

LaFrance, N.D.; Drew, H.H.; Walser, M.

1988-01-01

In order to determine the best method for routine measurement of glomerular filtration rate (GFR) in severe renal failure, we compared simultaneously the urinary clearances of [/sup 99m/Tc] diethylenetriaminepentaacetic acid (DTPA) (UD), [ 125 I]iothalamate (UI), 24-hr creatinine clearance (UC) and plasma clearance of [/sup 99m/Tc]DTPA (PD), based on three plasma samples. In 60 studies in 22 patients with serum creatinine values of 2 to 8 mg/dl, UD and UI were almost identical: UD = 0.358 +/- 0.976 UI +/- 0.87 ml/min, r = 0.990. However, PD overestimated UD by a large and variable extent: PD = 11.3 +/- 0.843 UD +/- 5.5 ml/min, r = 0.694, and was inconsistent in sequential measurements in individual patients. UC also overestimated urinary isotope clearance: UC = 4.2 + 0.95 UI +/- 3.9 ml/min, r = 0.865. Sequential measurements of GFR in five patients with severe but stable renal failure (mean GFR 5.9 ml/min) showed an average standard deviation of only 0.83 ml/min. Thus both UD and UI appear to be reliable and precise measures of GFR in severe renal failure

MR velocity mapping measurement of renal artery blood flow in patients with impaired kidney function

DEFF Research Database (Denmark)

Cortsen, M; Petersen, L.J.; Stahlberg, F

1996-01-01

Renal blood flow (RBF) was measured in 9 patients with chronic impaired kidney function using MR velocity mapping and compared to PAH clearance and 99mTc-DTPA scintigraphy. An image plane suitable for flow measurement perpendicular to the renal arteries was chosen from 2-dimensional MR angiography....... MR velocity mapping was performed in both renal arteries using an ECG-triggered gradient echo pulse sequence previously validated in normal volunteers. Effective renal plasma flow was calculated from the clearance rate of PAH during constant infusion and the split of renal function was evaluated...... by 99mTc-DTPA scintigraphy. A reduction of RBF was found, and there was a significant correlation between PAH clearance multiplied by 1/(1-hematocrit) and RBF determined by MR velocity mapping. Furthermore, a significant correlation between the distribution of renal function and the percent distribution...

Modified Augmented Renal Clearance Score Predicts Rapid Piperacillin and Tazobactam Clearance in Critically Ill Surgery and Trauma Patients

Science.gov (United States)

2014-04-24

collision; VAP , ventilator-associated pneumonia. TABLE 2. PK Parameter Estimates for Free Piperacillin and Tazobactam in Patients Stratified by ARC Score...SOFA score are typically generated during routine care of the most severely ill patients . Positive screening test results (high ARC scores) can be...Modified Augmented Renal Clearance score predicts rapid piperacillin and tazobactam clearance in critically ill surgery and trauma patients Kevin S

Lithium clearance method and the renal response to low-dose dopamine in man

DEFF Research Database (Denmark)

Olsen, N V; Olsen, M H; Fogh-Andersen, N

1993-01-01

.00 hours on three different occasions. After an overnight fast, the subjects were water-loaded and clearance studies were started at 09.00 hours with a 1h baseline period and three 1h periods during dopamine infusion. 2. Baseline sodium clearance with placebo was 0.65 +/- 0.35 ml/min, but with lithium......-induced changes in effective renal plasma flow, glomerular filtration rate or osmolal clearance. Neither lithium nor dopamine influenced plasma concentrations of renin, aldosterone or atrial natriuretic peptide. 4. In conclusion, single test doses of lithium, as normally used in lithium clearance studies......1. The effect of a single dose of lithium on renal function before and during intravenous infusion of dopamine (3 micrograms min-1 kg-1) was investigated in 12 healthy males. In a double-blind and randomized design, 450mg or 600mg of lithium carbonate or placebo was administered orally at 22...

Lithium clearance method and the renal response to low-dose dopamine in man

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Olsen, M H; Fogh-Andersen, N

1993-01-01

.00 hours on three different occasions. After an overnight fast, the subjects were water-loaded and clearance studies were started at 09.00 hours with a 1h baseline period and three 1h periods during dopamine infusion. 2. Baseline sodium clearance with placebo was 0.65 +/- 0.35 ml/min, but with lithium...... in effective renal plasma flow, glomerular filtration rate or osmolal clearance. Neither lithium nor dopamine influenced plasma concentrations of renin, aldosterone or atrial natriuretic peptide. 4. In conclusion, single test doses of lithium, as normally used in lithium clearance studies, increase baseline......1. The effect of a single dose of lithium on renal function before and during intravenous infusion of dopamine (3 micrograms min-1 kg-1) was investigated in 12 healthy males. In a double-blind and randomized design, 450mg or 600mg of lithium carbonate or placebo was administered orally at 22...

Longitudinal Associations among Renal Urea Clearance-Corrected Normalized Protein Catabolic Rate, Serum Albumin, and Mortality in Patients on Hemodialysis.

Science.gov (United States)

Eriguchi, Rieko; Obi, Yoshitsugu; Streja, Elani; Tortorici, Amanda R; Rhee, Connie M; Soohoo, Melissa; Kim, Taehee; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar

2017-07-07

There are inconsistent reports on the association of dietary protein intake with serum albumin and outcomes among patients on hemodialysis. Using a new normalized protein catabolic rate (nPCR) variable accounting for residual renal urea clearance, we hypothesized that higher baseline nPCR and rise in nPCR would be associated with higher serum albumin and better survival among incident hemodialysis patients. Among 36,757 incident hemodialysis patients in a large United States dialysis organization, we examined baseline and change in renal urea clearance-corrected nPCR as a protein intake surrogate and modeled their associations with serum albumin and mortality over 5 years (1/2007-12/2011). Median nPCRs with and without accounting for renal urea clearance at baseline were 0.94 and 0.78 g/kg per day, respectively (median within-patient difference, 0.14 [interquartile range, 0.07-0.23] g/kg per day). During a median follow-up period of 1.4 years, 8481 deaths were observed. Baseline renal urea clearance-corrected nPCR was associated with higher serum albumin and lower mortality in the fully adjusted model ( P trend urea clearance-corrected nPCR during the first 6 months was also associated with attaining high serum albumin (≥3.8 g/dl) and lower mortality ( P trend urea clearance, higher levels of renal urea clearance-corrected nPCR consistently showed lower mortality risk. Among incident hemodialysis patients, higher dietary protein intake represented by nPCR and its changes over time appear to be associated with increased serum albumin levels and greater survival. nPCR may be underestimated when not accounting for renal urea clearance. Compared with the conventional nPCR, renal urea clearance-corrected nPCR may be a better marker of mortality. Copyright © 2017 by the American Society of Nephrology.

Augmented Renal Clearance in Critical Illness: An Important Consideration in Drug Dosing

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Sherif Hanafy Mahmoud

2017-09-01

Full Text Available Augmented renal clearance (ARC is a manifestation of enhanced renal function seen in critically ill patients. The use of regular unadjusted doses of renally eliminated drugs in patients with ARC might lead to therapy failure. The purpose of this scoping review was to provide and up-to-date summary of the available evidence pertaining to the phenomenon of ARC. A literature search of databases of available evidence in humans, with no language restriction, was conducted. Databases searched were MEDLINE (1946 to April 2017, EMBASE (1974 to April 2017 and the Cochrane Library (1999 to April 2017. A total of 57 records were included in the present review: 39 observational studies (25 prospective, 14 retrospective, 6 case reports/series and 12 conference abstracts. ARC has been reported to range from 14–80%. ARC is currently defined as an increased creatinine clearance of greater than 130 mL/min/1.73 m2 best measured by 8–24 h urine collection. Patients exhibiting ARC tend to be younger (<50 years old, of male gender, had a recent history of trauma, and had lower critical illness severity scores. Numerous studies have reported antimicrobials treatment failures when using standard dosing regimens in patients with ARC. In conclusion, ARC is an important phenomenon that might have significant impact on outcome in critically ill patients. Identifying patients at risk, using higher doses of renally eliminated drugs or use of non-renally eliminated alternatives might need to be considered in ICU patients with ARC. More research is needed to solidify dosing recommendations of various drugs in patients with ARC.

Reliability of two different methods, whole body measurement and shoulder probe measurement, as judged from determinations of the renal clearance of orthoiodine hippuric acid. Methodenvergleich von Ganzkoerper- und Schultersonden-Messtechnik bei der nuklearmedizinischen Nierenclearance-Bestimmung mit Ortho-Jod-Hippursaeure

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Roth, A

1983-05-06

This retrospective study was based on 1300 patients subjected to a series of radiopharmaceutical renal function studies, during which parallel determinations of the renal clearance rate were carried out using whole body measurements and shoulder probe measurements. It was the aim of this analysis to assess the reliability of shoulder probe measurements as compared to that of whole body measurements as well as their suitability for the diagnosis of postural perfusion disorders associated with nephroptosis and to define the generally acceptable normal ranges of the clearance of ortho-iodine hippuric acid on the basis of age and sex groups. As long as the values measured remained within normal limits, no major differences were discernable between the two methods. In reduced renal function, however, the shoulder probe measurements were biassed in a consistent way and tended to an overestimation of the renal performance that was proportionate to the degree of insufficiency. The intra-assay variations observed for the two methods did not differ from each other at a statistically significant level. The systematic error seen in connection with the shoulder probe measurements can in fact be easily eliminated. This method also offers the advantage of greater simplicity and can be carried out with the patient being in an upright position. Its suitability for the detection of postural perfusion disorders still remains to be proven in further studies. The results of the study are of clinical relevance inasfar as it was possible to determine lower limits of OJH clearance for the individual age and sex groups.

TGF-beta1 immunohistochemistry and promoter methylation in chronic renal failure rats treated with Uremic Clearance Granules.

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Cheng-Bin Chen

2010-08-01

Full Text Available The aim of the study was the explain the mechanism related to therapeutic effects of Uremic Clearance Granules (Niaoduqing Keli in Chinese on adenine-induced Chronic Renal Failure in rats. Thirty 8-week-old male Wistar rats were selected and randomly divided in to 3 groups: Normal Control Group (NCGconsisted of 10 rats, Chronic Renal Failure Pathological Control Group (PCG 10 rats, and Uremic Clearance Granules Treatment Group (UCG 10 rats. Each rat in PCG and UCG was fed with adenine-enriched diets, containing 10 g adenine per kg food for 6 weeks. After fed with adenine, each rat in UCG was administered orally with 2 ml solution of Uremic Clearance Granules for 6 weeks. The concentration of Uremic Clearance Granules solution was 0.42 g/ml which was 10 times of human. On days 42 and 84, the serum levels of creatinine, Blood Urea Nitrogen and homocysteine were determined. The methylation of TGFbeta1 promoter was tested by methylation-specific PCR. TGF-beta1 mRNA and protein expression in rat renal cortex were analyzed by real-time RT-PCR and Immunohistochemistry. (1 Experimented on model of Chronic Renal Failure in rats, the preparation was proved to be able to reduce serum creatinine, Blood Urea Nitrogen, and homocysteine (p<0.05, improve renal function. (2 The expression of TGF-beta1 in mRNA and protein level were down-regulated. (3 TGF-beta1 promoter was demethylated at some loci in PCG, and was recovered in UCG. After treatment with Uremic Clearance Granules, the Chronic Renal Failure Wistar rat's kidney function was recovered. The recovery may be result of the remethylation of TGF-beta1 promoter and then lead to TGF-beta1 be transcripted and translated normally. The experimental study explain the molecular mechanism by which Uremic Clearance Granules treat Chronic Renal Failure.

RENAL CLEARANCE AND URINARY EXCRETION OF KANAMYCIN IN DOMESTIC RUMINANT SPECIES

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I. JAVED, Z. U. RAHMAN, F. H. KHAN, F. MUHAMMAD, Z. IQBAL AND B. ASLAM

2006-01-01

Full Text Available Species dependent geonetical differences in renal clearance and urinary excretion of kanamycin were investigated in adult female buffaloes, cows, sheep and goats. The drug was administered as a single intravenous dose (5 mg/kg b.wt. Blood and urine samples were collected at various time intervals after drug administration. The plasma and urine concentrations of the drug were determined using the microbiological assay. The mean (± SE values for endogenous creatinine clearance (an index of glomerular filtration rate were 0.77 ± 0.05, 0.49 ± 0.07, 0.81 ± 0.07 and 0.98 ± 0.13 ml/min.kg in buffaloes, cows, sheep and goats, respectively. Experiments regarding kidney handling of kanamycin in these ruminant species revealed respective values of renal clearance as 0.08 ± 0.01, 0.07 ± 0.01, 0.19 ± 0.02 and 0.23 ± 0.04 ml/min.kg. Besides glomerular filtration, kanamycin was reabsorbed from the renal tubules of all ruminant species and actively secreted into the renal tubules of buffaloes and goats. The cumulative percentages of intravenous dose of kanamycin excreted through urine during 12 hours in buffaloes, cows, sheep and goats were 4.31 ± 0.37, 2.53 ± 0.30, 11.0 ± 1.04 and 15.8 ± 2.22, respectively. This species variation in the percentage of urinary excretion in these domestic ruminants coincides with their respective glomerular filtration rates, being the highest in goats, lowest in cows and intermediate in sheep and buffaloes.

Measurement of single kidney contrast media clearance by multiphasic spiral computed tomography: preliminary results

International Nuclear Information System (INIS)

Hackstein, N.; Puille, M.F.; Bak, Benjamin H.; Scharwat, Oliver; Rau, W.S.

2001-01-01

Objective. We present preliminary results of a new method (hereinafter called 'CT-clearance') to measure single kidney contrast media clearance by performing multiphasic helical CT of the kidneys. CT-clearance was calculated according to an extension of the Patlak-Plot. In contrast to prior investigators, who repeatedly measured a single slice, this method makes it possible to calculate single kidney clearance from at least three spiral CTs, utilizing the whole kidney volume. Methods. Spiral CT of the kidneys was performed unenhanced and about 30 and 100 s after administration of about 120 ml iopromide. Sum-density of the whole kidneys and aortic density was calculated from this data. Using this data, renal clearance of contrast media was calculated by CT-clearance in 29 patients. As reference, Serum-clearance was calculated in 24 patients by application of a modified one-exponential slope model. Information on the relative kidney function was gained by renal scintigraphy with Tc99m-MAG-3 or Tc99m-DMSA in 29 patients. Results. Linear regression analysis revealed a correlation coefficient of CT-clearance with Serum-clearance of r=0.78 with Cl (CT) [ml/min]=22.2+1.03 * Cl (serum), n=24. Linear regression of the relative kidney function (rkf) of the right kidney calculated by CT-clearance compared to scintigraphy results provided a correlation coefficient r=0.89 with rkf(CT)[%]=18.6+0.58 * rkf(scintigraphy), n=29. Conclusion. The obtained results of contrast media clearance measured by CT-clearance are in the physiological range of the parameter. Future studies should be performed to improve the methodology with the aim of higher accuracy. More specifically, better determination of the aortic density curve might improve the accuracy

Augmented renal clearance is not a risk factor for mortality in Enterobacteriaceae bloodstream infections treated with appropriate empiric antimicrobials.

Science.gov (United States)

Burnham, Jason P; Micek, Scott T; Kollef, Marin H

2017-01-01

The main objective of the study was to assess whether augmented renal clearance was a risk factor for mortality in a cohort of patients with Enterobacteriaceae sepsis, severe sepsis, or septic shock that all received appropriate antimicrobial therapy within 12 hours. Using a retrospective cohort from Barnes-Jewish Hospital, a 1,250-bed teaching hospital, we collected data on individuals with Enterobacteriaceae sepsis, severe sepsis, and septic shock who received appropriate initial antimicrobial therapy between June 2009 and December 2013. Clinical outcomes were compared according to renal clearance, as assessed by Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas, sepsis classification, demographics, severity of illness, and comorbidities. We identified 510 patients with Enterobacteriaceae bacteremia and sepsis, severe sepsis, or septic shock. Sixty-seven patients (13.1%) were nonsurvivors. Augmented renal clearance was uncommon (5.1% of patients by MDRD and 3.0% by CKD-EPI) and was not associated with increased mortality. Our results are limited by the absence of prospective determination of augmented renal clearance. However, in this small cohort, augmented renal clearance as assessed by MDRD and CKD-EPI does not seem to be a risk factor for mortality in patients with Enterobacteriaceae sepsis. Future studies should assess this finding prospectively.

Measurement of renal function with /sup 111/In-DTPA in dogs

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Saha, G B [Arkansas Univ., Little Rock (USA). Medical Center; Farrer, P A

1977-07-01

The renal clearances of /sup 111/In-DTPA were measured and compared with those of /sup 125/I-iothalamate in dogs using three methods: (a) constant infusion method, (b) single injection UV/P method, and (c) single injection slope method. The renal clearances of /sup 111/In-DTPA were on the average 9% higher than those of /sup 125/I-iothalamate. Its urinary excretion was approximately 50% at 1 hr and about 80% at 4 hr, and biliary excretion was negligible. Sequential scintiphotography of the renal system in dogs revealed the flow of the tracer through the kidneys, and excretion into the ureter and bladder.

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...

Avaliação renal de hipertensos pela clearance de creatinina num centro de saúde de Teresina-PI, Brasil Evaluación renal de hipertensos en el aclaramiento de creatinina en un centro sanitario de Teresina- PI, Brasil Evaluation of renal hypertensive by creatinine clearance in a health center in Teresina-pi, Brazil

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Dinah Sá Rezende Neta

2012-03-01

hypertension by means of creatinine clearance, starting with measurement of serum creatinine. The study had a quantitative approach, developed at Porto Alegre Health Center. Data collection was carried out in nursing consultations using serum creatinine measurements. After the calculation of creatinine clearance utilizing the Cockcroft-Gault equation, patients were classified in one of the six phases of chronic renal disorder. The results revealed that 74% of the sample had renal damage, which shows how important is the periodic assessment of renal function of patients with hypertension so that they can be monitored with regard to the progression of their chronic renal disorder.

Spontaneous Clearance of Hepatitis C after Liver and Renal Transplantation

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CH Dale

2009-01-01

Full Text Available Spontaneous clearance of hepatitis C virus (HCV is rare in immunocompromised patients, such as those who have undergone organ transplantation. It has been recognized that patients receiving liver transplantation for HCV-related disease have decreased graft and patient survival compared with those transplanted for other etiologies. There is a growing trend toward treating HCV recurrence aggressively after liver transplantation. For other organ transplant recipients with concurrent HCV, treatment is not often an option, given the high rates of graft rejection and loss secondary to interferon and its immunomodulatory effects. Although spontaneous clearance of HCV has been reported in recipients of solitary liver and renal transplants, a common factor arising in these cases has been previous exposure to interferon. To date, no reports of spontaneous clearance of HCV RNA have been reported in a multiorgan transplant recipient. A case of spontaneous clearance of HCV RNA in an immunocompromised patient, within five months of simultaneous liver and kidney retransplantation is described. Importantly, this patient had no previous exposure to interferon.

Four hour creatinine clearance is better than plasma creatinine for monitoring renal function in critically ill patients

Science.gov (United States)

2012-01-01

Introduction Acute kidney injury (AKI) diagnosis is based on an increase in plasma creatinine, which is a slowly changing surrogate of decreased glomerular filtration rate. We investigated whether serial creatinine clearance, a direct measure of the glomerular filtration rate, provided more timely and accurate information on renal function than serial plasma creatinine in critically ill patients. Methods Serial plasma creatinine and 4-hour creatinine clearance were measured 12-hourly for 24 hours and then daily in 484 patients. AKI was defined either as > 50% increase in plasma creatinine from baseline, or > 33.3% decrease in creatinine clearance. The diagnostic and predictive performance of the two AKI definitions were compared. Results Creatinine clearance decrease diagnosed AKI in 24% of those not diagnosed by plasma creatinine increase on entry. These patients entered the ICU sooner after insult than those diagnosed with AKI by plasma creatinine elevation (P = 0.0041). Mortality and dialysis requirement increased with the change in creatinine clearance-acute kidney injury severity class (P = 0.0021). Amongst patients with plasma creatinine creatinine clearance improved the prediction of AKI considerably (Net Reclassification Improvement 83%, Integrated Discrimination Improvement 0.29). On-entry, creatinine clearance associated with AKI severity and duration (P 33.3% decrease in creatinine clearance over the first 12 hours was associated with a 2.0-fold increased relative risk of dialysis or death. Conclusions Repeated 4-hour creatinine clearance measurements in critically ill patients allow earlier detection of AKI, as well as progression and recovery compared to plasma creatinine. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN012606000032550. PMID:22713519

Effects and outcome of Tamsulosin more than just stone clearance after extracorporeal shock wave lithotripsy for renal calculi

International Nuclear Information System (INIS)

Qadri, S. S. U.; Khalid, S. E.; Mahmud, S. M.

2014-01-01

Objective: To determine the effect of Tamsulosin, as adjunctive medical therapy after Extracorporeal Shock Wave Lithotripsy for renal stones on rate of stone clearance, clearance time, pain intensity during stone clearance, steinstrasse formation and auxiliary surgical intervention required. Method: A prospective randomized controlled study was carried out in 120 patients who underwent ESWL for renal stones of 0.5-2.0 cm. They were randomized into study and control group in which Tamsulosin 0.4mg/day was given in former as an adjunctive medical therapy. All patients underwent ESWL every 2 weeks until complete stone clearance for 8 weeks. The parameters assessed were stone clearance, clearance time, pain intensity and effect on steinstrasse. Results: Of the 120 patients 60 were in each group. The stone clearance rate was greater in study than in control group, 58(96.7%) vs. 48(80%) respectively, (p<0.004). The mean stone clearance time was observed earlier in study group as compared to control group with significant statistical difference in stone size between 0.6-1.5 cm. The mean intensity of pain patients experienced according to Visual analogue scale (VAS) was significantly less in study group (p<0.002). The rate of steinstrasse formation was observed to be higher in control than in study group 15(25%) vs 6(10%) respectively(p<0.003), while its spontaneous clearance was higher in study group than in control group 83.3% vs 33.3% (p<0.03). Conclusion: Tamsulosin significantly increases stone clearance after shock wave lithotripsy for renal stones. It also appeared to facilitate earlier stone clearance, reduces severity of pain, reduces the incidence of steinstrasse formation and tends to facilitate its spontaneous clearance. (author)

Technetium-99m mercaptoacetyltriglycine clearance values in children with minimal renal disease: can a normal range be determined?

International Nuclear Information System (INIS)

Meyer, G.; Hahn, K.; Piepsz, A.; Kolinska, J.; Lepej, J.; Sixt, R.

1998-01-01

Use of technetium-99m labelled mercaptoacetyltriglycine ( 99m Tc-MAG3) simplifies and improves the quantification of renal clearance in children by virtue of its permanent availability, good imaging properties and low radiation exposure. Due to the lack of reference values for 99m Tc-MAG3 clearance in children, the Paediatric Task Group of the EANM initiated a multicentre study to evaluate 99m Tc-MAG3 clearance values in children with minimal renal disease. One hundred and twenty-five children aged between 12 months and 17 years, classified as renally healthy using defined diagnostic criteria, were included in the study. 99m Tc-MAG3 clearance was calculated using an algorithm on the basis of a single blood sample taken at any time between 30 and 40 min after tracer injection. In addition, the absolute 99m -Tc-MAG3 clearance values were normalized to body surface area. For further evaluation the children were classified into several groups according to age. There was a continuous increase in non-corrected 99m Tc-MAG3 clearance values from the age of 1 year up to the age of 17 years (mean value 8 years: 208±66 ml/min). Normal clearance values for adults were achieved by the age of 8 years. Analysis of the relationship between non-corrected clearance and age yielded a correlation coefficient of r=0.7. When these absolute clearance values were normalized to body surface area, we found nearly constant clearance values for all age groups, with a mean clearance value of 315±114 ml/min x 1.73 m 2 . The correlation coefficient for the relationship between normalized clearance and age was r=0.28. In conclusion, the clearance of 99m Tc-MAG3 increases continuously throughout childhood into adolescence due to the maturation and growth of the kidney. After normalization of the absolute clearance to body surface area, no correlation between clearance and age could be proven. (orig.)

Rapid blood clearance and lack of long-term renal toxicity of 177Lu-DOTATATE enables shortening of renoprotective amino acid infusion

International Nuclear Information System (INIS)

Kashyap, Raghava; Eu, Peter; Jackson, Price; Hofman, Michael S.; Hicks, Rodney J.; Beauregard, Jean-Mathieu; Zannino, Diana

2013-01-01

The aim of the study was to investigate the feasibility of shortening the recommended 4-h renoprotective amino acid infusion in patients receiving peptide receptor chemoradionuclide therapy (PRCRT) using radiosensitizing 5-fluorouracil. We evaluated the clearance of radiopeptide from the blood, long-term nephrotoxicity in patients undergoing PRCRT with the conventional 4-h amino acid infusion and renal uptake in patients receiving an abbreviated infusion. The whole-blood clearance of 177 Lu-DOTA-octreotate (LuTate) was measured in 13 patients receiving PRCRT. A retrospective analysis of short-term and long-term changes in glomerular filtration rate (GFR) in 96 consecutive patients receiving a 4-h infusion was performed. Renal LuTate retention estimated using quantitative SPECT/CT in 22 cycles delivered with a 2.5-h amino acid infusion was compared with that in 72 cycles with the 4-h infusion. LuTate demonstrated biexponential blood clearance with an initial clearance half-time of 21 min. Approximately 88 % of blood activity was cleared within 2 h. With the 4-h protocol, there was no significant change in GFR (1.2 ml/min mean increase from baseline; 95 % CI -6.9 to 4.4 ml/min) and no grade 3 or 4 nephrotoxicity at the end of induction PRCRT. The long-term decline in GFR after a median follow up of 22 months was 2.2 ml/min per year. There was no significant difference in the renal LuTate retention measured in patients receiving a 2.5-h amino acid infusion compared to those who had a 4-h infusion. The greatest renal exposure to circulating radiopeptide occurs in the first 1 - 2 h after injection. This, combined with the safety of LuTate PRCRT, allows consideration of an abbreviated amino acid infusion, increasing patient convenience and reducing human resource allocation. (orig.)

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

To establish appropriate standard circumstances for lithium clearance measurements, a study was undertaken in 12 healthy volunteers. In each subject, the glomerular filtration rate (GFR), as estimated by [51Cr]EDTA plasma clearance, and the renal clearances of lithium, sodium and potassium were...... measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

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...

Diagnostic value of renal clearance techniques using iodo-hippuran /sup 131/I and /sup 99m/-DTPA

Energy Technology Data Exchange (ETDEWEB)

Heidenreich, P; Hoer, G [Technische Univ. Muenchen (Germany, F.R.). Nuklearmedizinische Klinik und Poliklinik

1976-01-01

Methods and clinical indications of divided renal clearance determination using /sup 131/I-hippuran are presented and their value as a diagnostic tool in urology is shown by two case reports. For quantitative assessment of renal function we prefer the whole body clearance (with partial shielding of kidneys and bladder) which obviates the necessity of the theoretical assumption of compartmental distribution of radiopharmaceuticals. Using simplified clearance techniques only based on analysis of plasma disappearance curves (slope clearance one- and two-compartment model), clinically useful results are also obtainable, especially in follow up studies. The evaluation of tubular and glomerular kidney function by simultaneous application of /sup 131/I-hippuran and sup(99m)Tc-DTPA is suitable for estimation of filtration fraction in patients with urological and nephrological diseases. Even with regard to therapy and follow up studies of urinary tract tuberculosis, remarkable dignostic informations may be achieved.

Rapid blood clearance and lack of long-term renal toxicity of {sup 177}Lu-DOTATATE enables shortening of renoprotective amino acid infusion

Energy Technology Data Exchange (ETDEWEB)

Kashyap, Raghava; Eu, Peter [Centre for Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne (Australia); Jackson, Price [Peter MacCallum Cancer Centre, Department of Physical Sciences, Melbourne (Australia); Hofman, Michael S.; Hicks, Rodney J. [Centre for Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne (Australia); The University of Melbourne, Departments of Medicine and Radiology, Melbourne (Australia); Beauregard, Jean-Mathieu [Universite Laval, Department of Radiology, Quebec City (Canada); Zannino, Diana [Peter MacCallum Cancer Centre, Department of Biostatistics and Clinical Trials, Melbourne (Australia)

2013-12-15

The aim of the study was to investigate the feasibility of shortening the recommended 4-h renoprotective amino acid infusion in patients receiving peptide receptor chemoradionuclide therapy (PRCRT) using radiosensitizing 5-fluorouracil. We evaluated the clearance of radiopeptide from the blood, long-term nephrotoxicity in patients undergoing PRCRT with the conventional 4-h amino acid infusion and renal uptake in patients receiving an abbreviated infusion. The whole-blood clearance of {sup 177}Lu-DOTA-octreotate (LuTate) was measured in 13 patients receiving PRCRT. A retrospective analysis of short-term and long-term changes in glomerular filtration rate (GFR) in 96 consecutive patients receiving a 4-h infusion was performed. Renal LuTate retention estimated using quantitative SPECT/CT in 22 cycles delivered with a 2.5-h amino acid infusion was compared with that in 72 cycles with the 4-h infusion. LuTate demonstrated biexponential blood clearance with an initial clearance half-time of 21 min. Approximately 88 % of blood activity was cleared within 2 h. With the 4-h protocol, there was no significant change in GFR (1.2 ml/min mean increase from baseline; 95 % CI -6.9 to 4.4 ml/min) and no grade 3 or 4 nephrotoxicity at the end of induction PRCRT. The long-term decline in GFR after a median follow up of 22 months was 2.2 ml/min per year. There was no significant difference in the renal LuTate retention measured in patients receiving a 2.5-h amino acid infusion compared to those who had a 4-h infusion. The greatest renal exposure to circulating radiopeptide occurs in the first 1 - 2 h after injection. This, combined with the safety of LuTate PRCRT, allows consideration of an abbreviated amino acid infusion, increasing patient convenience and reducing human resource allocation. (orig.)

A computer program for unilateral renal clearance calculation by a modified Oberhausen method

International Nuclear Information System (INIS)

Brueggemann, G.

1980-01-01

A FORTAN program is presented which, on the basis of data obtained with NUKLEOPAN M, calculates the glomerular filtration rate with sup(99m)Tc-DTPA, the unilateral effective renal plasma flow with 131 I-hippuran, and the parameters for describing the isotope rephrogram (ING) with 131 I-hippuran. The results are calculated fully automatically upon entry of the data, and the results are processed and printed out. The theoretical fundamentals of ING and whole-body clearance calculation are presented as well as the methods available for unilateral clearance calculation, and the FORTAN program is described in detail. The standard values of the method are documented, as well as a comparative gamma camera study of 48 patients in order to determine the accuracy of unilateral imaging with the NUKLEOPAN M instrument, a comparison of unilateral clearances by the Oberhausen and Taplin methods, and a comparison between 7/17' plasma clearance and whole-body clearance. Problems and findings of the method are discussed. (orig./MG) [de

Creatinine clearance test

Science.gov (United States)

Serum creatinine clearance; Kidney function - creatinine clearance; Renal function - creatinine clearance ... Creatinine is a chemical waste product of creatine. Creatine is a chemical the body makes to supply ...

Significance of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy in nonobstructive isolated renal pelvic stones.

Science.gov (United States)

Sozen, Sinan; Kupeli, Bora; Acar, Cenk; Gurocak, Serhat; Karaoglan, Ustunol; Bozkirli, Ibrahim

2008-05-01

To investigate the probable effect of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy (SWL) in patients with nonobstructive renal pelvic stones. The clinical records of patients with isolated renal pelvic stones who underwent SWL between 1996 and 2005 were reviewed. After excluding patients with obstruction leading to dilatation, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 153 patients were enrolled in the study. Lower pole infundibulopelvic angle (IPA) and infundibular length and width were measured from intravenous urography. Patients were classified into three groups according to stone burden (group 1, renal pelvis, and both in 50 (32.6%), 29 (18.9%), and 8 (5.2%) patients, respectively. There was no statistically significant difference in pelvicaliceal anatomic features except narrower IPA (P=0.02) in group 1 patients with residual stones. The falling of stone fragments to the lower calix in spite of the ureter whether clinically significant or not after SWL of pelvic stones initially seems to be related to stone burden rather than lower caliceal anatomy. However, existence of a more narrow IPA in group 1 patients with residual fragments led us to believe that lower-pole IPA can play a role in stone clearance, especially for smaller stones, probably because of smaller residual fragment size or the more mobile nature of the primary stone.

Measurement of Effective Renal Plasma Flow: Evaluation of Clinical Uses in Combination with Renography

Energy Technology Data Exchange (ETDEWEB)

Mahadev, V. [Department of Radiotherapy and Nuclear Medicine, General Hospital, Kuala Lumpur (Malaysia)

1971-02-15

A comparison of techniques for measuring the renal clearance of Hippuran using a single injection of {sup 131}I sodium orthoiodohippurate in 30 normal subjects and 49 patients showed that a simplified technique using limited samples of blood gave comparable results to more complicated blood and external monitoring techniques without significant loss of accuracy. The clearance value in normal subjects was 645 ml/1.73 m{sup 2} ({+-} 108 ml) and is comparable with results obtained elsewhere. Together with a renogram examination this measurement enables more information to be obtained and helps to distinguish vascular and parenchymal disorders from purely obstructive lesions. It may be useful in the problem of renal tuberculosis and in distinguishing benign kidney lesions from malignant. (author)

PAH clearance after renal ischemia and reperfusion is a function of impaired expression of basolateral Oat1 and Oat3.

Science.gov (United States)

Bischoff, Ariane; Bucher, Michael; Gekle, Michael; Sauvant, Christoph

2014-02-01

Determination of renal plasma flow (RPF) by para-aminohippurate (PAH) clearance leads to gross underestimation of this respective parameter due to impaired renal extraction of PAH after renal ischemia and reperfusion injury. However, no mechanistic explanation for this phenomenon is available. Based on our own previous studies we hypothesized that this may be due to impairment of expression of the basolateral rate limiting organic anion transporters Oat1 and Oat3. Thus, we investigated this phenomenon in a rat model of renal ischemia and reperfusion by determining PAH clearance, PAH extraction, PAH net secretion, and the expression of rOat1 and rOat3. PAH extraction was seriously impaired after ischemia and reperfusion which led to a threefold underestimation of RPF when PAH extraction ratio was not considered. PAH extraction directly correlated with the expression of basolateral Oat1 and Oat3. Tubular PAH secretion directly correlated with PAH extraction. Consequently, our data offer an explanation for impaired renal PAH extraction by reduced expression of the rate limiting basolateral organic anion transporters Oat1 and Oat3. Moreover, we show that determination of PAH net secretion is suitable to correct PAH clearance for impaired extraction after ischemia and reperfusion in order to get valid results for RPF.

A Simple Method to Measure Renal Function in Swine by the Plasma Clearance of Iohexol

Science.gov (United States)

Luis-Lima, Sergio; García-Contreras, Consolación; Carrara, Fabiola; Negrín-Mena, Natalia; Jiménez-Sosa, Alejandro; Jiménez-Hernández, Hugo; Porrini, Esteban

2018-01-01

There is no simple method to measure glomerular filtration rate (GFR) in swine, an established model for studying renal disease. We developed a protocol to measure GFR in conscious swine by using the plasma clearance of iohexol. We used two groups, test and validation, with eight animals each. Ten milliliters of iohexol (6.47 g) was injected into the marginal auricular vein and blood samples (3 mL) were collected from the orbital sinus at different points after injection. GFR was determined using two models: two-compartment (CL2: all samples) and one-compartment (CL1: the last six samples). In the test group, CL1 overestimated CL2 by ~30%: CL2 = 245 ± 93 and CL1 = 308 ± 123 mL/min. This error was corrected by a first-order polynomial quadratic equation to CL1, which was considered the simplified method: SM = −47.909 + (1.176xCL1) − (0.00063968xCL12). The SM showed narrow limits of agreement with CL2, a concordance correlation of 0.97, and a total deviation index of 14.73%. Similar results were obtained for the validation group. This protocol is reliable, reproducible, can be performed in conscious animals, uses a single dose of the marker, and requires a reduced number of samples, and avoids urine collection. Finally, it presents a significant improvement in animal welfare conditions and handling necessities in experimental trials. PMID:29329247

A Simple Method to Measure Renal Function in Swine by the Plasma Clearance of Iohexol

Directory of Open Access Journals (Sweden)

Sergio Luis-Lima

2018-01-01

Full Text Available There is no simple method to measure glomerular filtration rate (GFR in swine, an established model for studying renal disease. We developed a protocol to measure GFR in conscious swine by using the plasma clearance of iohexol. We used two groups, test and validation, with eight animals each. Ten milliliters of iohexol (6.47 g was injected into the marginal auricular vein and blood samples (3 mL were collected from the orbital sinus at different points after injection. GFR was determined using two models: two-compartment (CL2: all samples and one-compartment (CL1: the last six samples. In the test group, CL1 overestimated CL2 by ~30%: CL2 = 245 ± 93 and CL1 = 308 ± 123 mL/min. This error was corrected by a first-order polynomial quadratic equation to CL1, which was considered the simplified method: SM = −47.909 + (1.176xCL1 − (0.00063968xCL12. The SM showed narrow limits of agreement with CL2, a concordance correlation of 0.97, and a total deviation index of 14.73%. Similar results were obtained for the validation group. This protocol is reliable, reproducible, can be performed in conscious animals, uses a single dose of the marker, and requires a reduced number of samples, and avoids urine collection. Finally, it presents a significant improvement in animal welfare conditions and handling necessities in experimental trials.

Perspectives on hypertension outcomes after single-stage clearance of a complete staghorn renal calculus

Directory of Open Access Journals (Sweden)

Ranjit Chaudhary

2017-01-01

Full Text Available A 55-year-old male presented, in June 2013, with left flank pain. Investigations revealed a complete staghorn stone. He had undergone two sittings of extracorporeal shock wave lithotripsy (ESWL in 2008 for left renal stone. One year subsequent to this, he was diagnosed with hypertension and diabetes. The management of complete staghorn stones in a single sitting is a difficult proposition. Percutaneous nephrolithotomy (PCNL is the gold standard to manage such stones. The patient was subjected to PCNL, and complete clearance was achieved in one sitting. On one-year follow-up, there was a significant reduction in blood pressure (BP and better glycemic control. Although there are several reports where hypertension has been reported after multiple sittings of ESWL, whether ESWL contributed to the genesis of hypertension and diabetes in this patient or it was simply incidental, cannot be stated with certainty. There was a significant reduction in the BP after complete stone removal, but there is uncertainty over the effect of total clearance of renal stones on hypertension, and we need to await the results of more controlled trials studying this phenomenon. A better glycemic control was perhaps achieved secondary to the eradication of recurrent urinary tract infections due to complete stone clearance.

Demonstration of Adaptive Functional Differences Seen in Kidneys Accompanying a Nonfunctioning/Hypofunctioning Partner, using Camera Based Tc 99m MAG3 Clearance Measurement Technique

Directory of Open Access Journals (Sweden)

Burcu Esen Akkaş

2012-08-01

Full Text Available Objective: The aim of this study was to demonstrate the functional compensation that occurs in kidneys which accompany a partner with total or partial loss of renal functioning mass, using camera-based Tc 99m MAG3 clearance technique. Material and Methods: Eighty five patients (43M, 42F, age: 44.8±12.6, range: 18-77 years with normal serum creatinine levels and normal (renal function<30%, (n=24, group 3: bilateral normal kidneys (n=38. The measured camera based Tc 99m MAG3 clearances of normal kidneys in each group were compared. Results: Total Tc 99m MAG3 clearances (mL/min/1.73m 2 were significantly lower in group 1 and group 2 compared to group 3 (281.5±46, 260.5±61.7 and 316.1±84, respectively. Highest isolated Tc 99m MAG3 clearances among normal functioning kidneys were observed in group 1 (281.5±45.6 followed by group 2 (204.4±55 and group 3 (157.5±44. Moderate negative correlation was detected between the Tc99m MAG3 clearances of normal kidneys and contralateral renal function (r=-0.5, p<0.001. Conclusion: Normal kidneys can compensate for the loss of contralateral kidney function via increasing their clearances, which seems to be dependent on the residual function of their partner. Camera based Tc 99m MAG3 clearance measurement is an objective method to demonstrate compensatory differences in renal function seen between kidneys with contralateral normofunctioning, hypofunctioning and nonfunctioning partner. (MIRT 2012;21:56-62

Passing through the renal clearance barrier: toward ultrasmall sizes with stable ligands for potential clinical applications

Directory of Open Access Journals (Sweden)

Zhang XD

2014-04-01

Full Text Available Xiao-Dong Zhang,1 Jiang Yang,2 Sha-Sha Song,1 Wei Long,1 Jie Chen,1 Xiu Shen,1 Hao Wang,1 Yuan-Ming Sun,1 Pei-Xun Liu,1 Saijun Fan11Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, People's Republic of China; 2Department of Biological Systems Engineering, University of Wisconsin-Madison, Madison, WI, USAAbstract: The use of nanoparticles holds promise for medical applications, such as X-ray imaging, photothermal therapy and radiotherapy. However, the in vivo toxicity of inorganic nanoparticles raises some concern regarding undesirable side effects which prevent their further medical application. Ultrasmall sub-5.5 nm particles can pass through the barrier for renal clearance, minimizing their toxicity. In this letter we address some recent interesting work regarding in vivo toxicity and renal clearance, and discuss the possible strategy of utilizing ultrasmall nanomaterials. We propose that small hydrodynamic sized nanoclusters can achieve both nontoxic and therapeutic clinical features.Keywords: in vivo clearance, gold nanoparticles, small size

Impact on creatinine renal clearance by the interplay of multiple renal transporters: a case study with INCB039110.

Science.gov (United States)

Zhang, Yan; Warren, Mark S; Zhang, Xuexiang; Diamond, Sharon; Williams, Bill; Punwani, Naresh; Huang, Jane; Huang, Yong; Yeleswaram, Swamy

2015-04-01

Serum creatinine is commonly used as a marker of renal function, but increases in serum creatinine might not represent changes in glomerular filtration rate (GFR). INCB039110 (2-(3-(4-(7H-pyrrolo[2,3-day]pyrimidin-4-yl)-1H-pyrazol-1-yl)-1-(1-(3-fluoro-2-(trifluoromethyl)isonicotinoyl)piperidin-4-yl)azetidin-3-yl)acetonitrile) is an inhibitor of the Janus kinases (JAKs) with selectivity for JAK1. In a phase 1 study, a modest and reversible increase in serum creatinine was observed after treatment with INCB039110. However, a dedicated renal function study with INCB039110, assessed by iohexol plasma clearance, conducted in healthy volunteers indicated no change in GFR. In vitro studies were therefore conducted to investigate the interaction of INCB039110 with five transporters that are likely involved in the renal clearance of creatinine. Cell systems expressing individual or multiple transporters were used, including a novel quintuple-transporter model OAT2/OCT2/OCT3/MATE1/MATE2-K. INCB039110 potently inhibited OCT2-mediated uptake of creatinine as well as MATE1-/MATE2-K-mediated efflux of creatinine. Given the interactions of INCB039110 with multiple transporters affecting creatinine uptake and efflux, an integrated system expressing all five transporters was sought; in that system, INCB039110 caused a dose-dependent decrease in transcellular transport of creatinine with weaker net inhibition compared with the effects on individual transporters. In summary, a molecular mechanism for the increase in serum creatinine by INCB039110 has been established. These studies also underline the limitations of using serum creatinine as a marker of renal function. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Creatinine measurements often yielded false estimates of progression in chronic renal failure

International Nuclear Information System (INIS)

Walser, M.; Drew, H.H.; LaFrance, N.D.

1988-01-01

In 9 of 22 observation periods (lasting an average of 15 months) in 17 patients with moderate to severe chronic renal failure (GFR 4 to 23 ml/min), rates of progression as estimated from the linear regression on time of 24-hour creatinine clearance (b1) differed significantly from rates of progression as estimated from the regression on time of urinary clearance of 99mTc-DTPA (b2), during all or part of the period of observation. b1 exceeded b2 in four cases and was less than b2 in the other five. Thus there were gradual changes in the fractional tubular secretion of creatinine in individual patients, in both directions. Owing to these changes, measurements of creatinine clearance gave erroneous impressions of the rate or existence of progression during all or a portion of the period of observation in nearly half of these patients. In the 22 studies as a group, using the entire periods of observation, b1 indicated significantly more rapid progression (by 0.18 +/- 0.06 ml/min/month, P less than 0.01) than did b2, and had a significantly greater variance. Measurements of progression based on the rate of change of reciprocal plasma creatinine (multiplied by an average rate of urinary creatinine excretion in each study) were equally misleading, even though less variable. We conclude that sequential creatinine measurements are often misleading as measures of progression and should, when feasible, be replaced by urinary clearance of isotopes in following patients with chronic renal failure

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.

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...

Usefulness of parametric renal clearance images in the assessment of basic risk factors for renalnal clearance images in the assessment of basic risk factors for renal scarring in children with recurrent urinary tract infections.

Science.gov (United States)

Pietrzak-Stelasiak, Ewa; Bieńkiewicz, Małgorzata; Woźnicki, Wojciech; Bubińska, Krystyna; Kowalewska-Pietrzak, Magdalena; Płachcińska, Anna; Kuśmierek, Jacek

2017-01-01

Clinically confirmed incidents of acute pyelonephritis (APN) following recurrent infections of urinary tract (UTI) form basic risk factors for renal scarring in children. Vesico-uretheral reflux (VUR) of higher grade is additional risk factor for this scarring. Opinions on diagnostic value of summed sequential images of renal uptake phase (SUM) of dynamic renal scintigraphy in detection of renal scars are diverse. However, several publications point to higher diagnostic efficacy of clearance parametric images (PAR) generated from this study. To establish a clinical value of parametric renal clearance images in detection of renal scarring. A prospective study was performed in a group of 91 children at the age of 4 to 18 years with recurrent UTI. Clinically documented incidents of APN were noted in 32 children: in 8 cases - one and in the remaining 24 - 2 to 5 (mean 3) incidents. In the remaining 59 patients only infections of the lower part of urinary tract were diagnosed. Static renal 99mTc-DMSA SPECT study and after 2-4 days dynamic renal studies (99mTc-EC) were performed in every patient not earlier than 6 months after the last documented incident of UTI. PAR images generated from a dynamic study by in-house developed software and SUM images were compared with a gold standard SPECT study. Percentages of children with detected renal scar(s) with SPECT and PAR methods amounted to 55% and 54%, respectively and were statistically significantly higher (p children with history of APN detected with SPECT and PAR methods were significantly more frequent than with infections of only lower part of urinary tract (72% vs. 46%; p = 0.017 and 69% vs. 46%; p = 0.036, respectively). A SUM method did not reveal statistically significant differences between frequencies of detection of scars in groups specified above - 38% vs. 27% (p = 0.31). Both SPECT and PAR methods showed also that frequencies of occurrence of renal scars in children with higher grades of VUR were higher than

Improved interpretation of renal-vein-renin-ratio by simultaneous determination of renal 131I-hippuric-acid-clearance-ratio in patients with renovascular hypertension

International Nuclear Information System (INIS)

Helber, A.; Boenner, G.; Hummerich, W.; Wambach, G.; Meurer, K.A.; Dvorak, K.; Lent, V.; Zehle, A.; Kaufmann, W.; Koeln Univ.; Staedtisches Krankenhaus Koeln-Merheim; Staedtisches Krankenhaus Koeln-Merheim; Koeln Univ.

1979-01-01

In patients with unilateral vascular kidney disease and hypertension, ratio of renal-vein-renin was compared with 131 I-Hippuric-acid clearance and change in blood pressure during Saralasininfusion. The ratio of renal-vein-renin was positively correlated with the ratio in renal plasma flow between the kidneys in all patients studied. The ratio of renins therefore is a result of two factors: The difference in renin secretion and the difference in blood flow in the two kidneys. In patients with angiotensin independent hypertension renin-ratios up to 2.0 were found without relevance to elevated blood pressure. When the difference in renal blood flow between both kidneys was small, even a slight difference in renal vein renin indicated hypertension related to increased renin secretion. (orig./AJ) [de

Comparison of renal clearance of 99mTc-DTPA and inulin 131I-hippurate and PAH as well as creatinine clearance in Wistar-rats

International Nuclear Information System (INIS)

Hagemann, J.; Li Min Su; Strangfeld, D.; Schuerer, M.; Siewert, H.; Pietsch, R.; Kruse, I.; Priem, F.

1988-01-01

Averages and standard deviations of 99m Tc-DTPA and 131 I-hippurate slope clearance were consecutively determined for 56 male Wistar rats, with a body-weight of 271 ± 69 g in a single investigation. Clearance of 99m Tc-DTPA was 17.4 ± 3.4, that of 131 I-hippurate was 34.3 ± 7.2 μl · s -1 per 100 g body weight. For 17 rats inulin and PAH clearances were determined after 3 days with the steady-state method with continuous infusion and 3-4 periods of urine collection. During the same periods endogeneous creatinine clearance was determined. 99m Tc-DTPA slope clearance correlated well with inulin clearance, also the hippurate with the PAH clearance. The high values of the filtration fraction, calculated from radioisotope and chemical methods, and the low PAH extraction of 42% lead to the conclusion, that PAH and hippurate are incompletely eliminated by the rat kidney from plasma and therefore are inadequate for determining renal blood flow in rats. Creatinine clearance was 4.7 ± 1.38 μl · s -1 per 100 g body weight, much lower than that of inulin and 99m Tc-DTPA. Therefore is assumed, that tubular reabsorption of creatinine occurs and creatinine clearance cannot serve for the evaluation of GFR in rats. For this, however, the clearance of 99m Tc-DTPA seems well applicable in Wistar rats. (author)

Comparison of renal clearance of 99mTc-DTPA and inulin, 131I-hippurate and PAH as well as of the creatinine clearance in Wistar rats

International Nuclear Information System (INIS)

Hagemann, J.; Li Min Su; Strangfeld, D.; Schuerer, M.; Siewert, H.; Pietsch, R.; Kruse, I.; Priem, F.

1988-01-01

Order of magnitude and standard deviation of 99m Tc-DTPA and 131 I-hippurate slope clearance were analyzed successively in 56 male Wistar rats. The clearance of 99m Tc-DTPA was 17.4 ± 3.43 μl · s -1 (100 g b-w) -1 , of 131 I-hippurate 34.3 ± 7.21 μl · s -1 (100 g b-w) -1 . In 17 rats inulin and PAH clearances were analyzed by steady state method with permanent infusion and 3 to 4 urine collection periods 3 days later. The endogeneous creatinine clearance was determined within the same periods. The 99m Tc-DTPA slope clearance corresponded to the inulin clearance, as well as the hippurate clearance to the PAH clearance. The high filtration fraction calculated from nuclear medicine and chemical clearance methods and the low PAH extraction (42%) let suggest that PAH and hippurate are eliminated only incompletely from plasma in rat kidney and are unsuitable for determination of renal blood supply in rats. The creatinine clearance with 4.7 ± 1.38 μl · s -1 (100 g b-w) -1 was far beneath the clearance of inulin and 99m Tc-DTPA, supposing that creatinine is reabsorbed tubularly in part and the creatinine clearance can not be used for valuation of the GFR in rats. However, for this the 99m Tc-DTPA clearance in Wistar rats seems to be well suited. (author)

[The equivalent renal urea clearance. Its relationship with mortality in chronic hemodialysed patients].

Science.gov (United States)

Barreneche, M; Carreras, R; Leanza, H J; Najún Zarazaga, C J

1999-01-01

The Equivalent Renal Urea Clearance (EKR) integrates the residual renal function (KR) and the dialysis dose (Kt/V). The present study was performed with these objectives: to calculate EKR in our hemodialysis (HD) patients during a three year follow up, to define its relationship with mortality and to compare its importance as a risk factor among others and to calculate actuarial survival. We analyzed 267 chronic HD patients. We measured Kt/V single pool, TACu, albumin, creatinine, hemoglobin and HD time and we calculated KR, EKR, KRc and EKRc (the last two corrected for V* 401--to compare clearances of different size patients). The EKRc median was 14.20 ml/min and it was taken as cut off point. The mortality OR was 2.17. The multivariated analysis showed, as independent mortality predictors, the albumin (the most significant), the EKRc and the HD time. The actuarial survival of EKRc, Kt/V and albumin showed marked similarity of their curves. The significant differences between the predictor curves began on the 2nd year of HD, for albumin they began in levels lesser than 3.5 g/dl and higher than 3.4 g/dl. Therefore, we consider that the best advantage of EKRc, compared to other parameters derived from the urea kinetics model, was the possibility to valuate the weekly HD adequation (once, twice or three times a week) and this, depending on the KR and the Kt/V of each HD treatment. Besides, the EKRc could also be used as adequacy criterion in CAPD considering daily Kt/V so that we could employ EKRc as adequacy parameter for both replacement therapies.

Clearance Laboratory - Capability and measurement sensitivity

Energy Technology Data Exchange (ETDEWEB)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-08-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

Clearance Laboratory - Capability and measurement sensitivity

International Nuclear Information System (INIS)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-09-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

Study to improve the precision of calculation of split renal clearance by gamma camera method using 99mTc-MAG3

International Nuclear Information System (INIS)

Mimura, Hiroaki; Tomomitsu, Tatsushi; Yanagimoto, Shinichi

1999-01-01

Both fundamental and clinical studies were performed to improve the precision with which split renal clearance is calculated from the relation between renal clearance and the total renal uptake rate by using 99m Tc-MAG 3 , which is mainly excreted into the proximal renal tubules. In the fundamental study, the most suitable kidney phantom threshold values for the extracted renal outline were investigated with regard to size, radioactivity, depth of the kidney phantom, and radioactivity in the background. In the clinical study, suitable timing to obtain additional images for making the ROI and the standard point for calculation of renal uptake rate were investigated. The results indicated that, although suitable threshold values were distributed from 25% to 45%, differences in size, solution activity, and the position of the phantom or BG activity did not have significant effects. Comparing 1-3 min with 2-5 min as the time for additional images for ROI, we found that renal areas using the former time showed higher values, and the correlation coefficient of the regression formula improved significantly. Comparison of the timing for the start of data acquisition with the end of the arterial phase as a standard point of calculating renal uptake rate showed improvement in the latter. (author)

A gene-gene interaction between polymorphisms in the OCT2 and MATE1 genes influences the renal clearance of metformin

DEFF Research Database (Denmark)

Hougaard Christensen, Mette Marie; Pedersen, Rasmus Steen; Stage, Tore Bjerregaard

2013-01-01

The aim of this study was to determine the association between the renal clearance (CL(renal)) of metformin in healthy Caucasian volunteers and the single-nucleotide polymorphism (SNP) c.808G>T (rs316019) in OCT2 as well as the relevance of the gene-gene interactions between this SNP and (a) the ...

Renal radioisotope clearance in an unselected group of diabetics - a tool for the early recognition of diabetic nephropathy

International Nuclear Information System (INIS)

Doschek, D.; Wulf, R.; Krause, F.J.; Kreiskrankenhaus Albstadt

1980-01-01

Our study in unselected patients with diabetes was undertaken to determine the relation between glomerular filtration rate (GFR) and renal plasma flow (RPF) according to the patient's age. The diagnostic work-up was done with patients in unselected disease states because a classification of all systemic manifestations of the diabetes was not possible. The lack of selection may therefore reduce the value of our statistical results. From age 55 onwards, there was a reduction in GFR and, to a lesser extent, in PRF esceeding that which was age-dependent. It is, therefore, recommended to check the clearance in all patients with diabetes older than 55 years. The clearance with radioisotopically labeled substances, being a very sensitive method for the evaluation of restricted renal function, may permit an early recognition of diabetic nephropathy. (orig.) [de

PAH clearance after renal ischemia and reperfusion is a function of impaired expression of basolateral Oat1 and Oat3

OpenAIRE

Bischoff, Ariane; Bucher, Michael; Gekle, Michael; Sauvant, Christoph

2014-01-01

Abstract Determination of renal plasma flow (RPF) by para‐aminohippurate (PAH) clearance leads to gross underestimation of this respective parameter due to impaired renal extraction of PAH after renal ischemia and reperfusion injury. However, no mechanistic explanation for this phenomenon is available. Based on our own previous studies we hypothesized that this may be due to impairment of expression of the basolateral rate limiting organic anion transporters Oat1 and Oat3. Thus, we investigat...

Megalin and cubilin are endocytic receptors involved in renal clearance of hemoglobin

DEFF Research Database (Denmark)

Gburek, Jakub; Verroust, Pierre J; Willnow, Thomas E

2002-01-01

-Sepharose affinity chromatography of solubilized renal brush-border membranes. Apparent dissociation constants of 1.7 microM for megalin and 4.1 microM for cubilin were determined by surface plasmon resonance analysis. The binding was calcium dependent in both cases. Uptake of fluorescence-labeled hemoglobin by BN......The kidney is the main site of hemoglobin clearance and degradation in conditions of severe hemolysis. Herein it is reported that megalin and cubilin, two epithelial endocytic receptors, mediate the uptake of hemoglobin in renal proximal tubules. Both receptors were purified by use of hemoglobin...... not affect the uptake. By use of immunohistochemistry, it was demonstrated that uptake of hemoglobin in proximal tubules of rat, mouse, and dog kidneys occurs under physiologic conditions. Studies on normal and megalin knockout mouse kidney sections showed that megalin is responsible for physiologic...

The rebirth of interest in renal tubular function.

Science.gov (United States)

Lowenstein, Jerome; Grantham, Jared J

2016-06-01

The measurement of glomerular filtration rate by the clearance of inulin or creatinine has evolved over the past 50 years into an estimated value based solely on plasma creatinine concentration. We have examined some of the misconceptions and misunderstandings of the classification of renal disease and its course, which have followed this evolution. Furthermore, renal plasma flow and tubular function, which in the past were estimated by the clearance of the exogenous aryl amine, para-aminohippurate, are no longer measured. Over the past decade, studies in experimental animals with reduced nephron mass and in patients with reduced renal function have identified small gut-derived, protein-bound uremic retention solutes ("uremic toxins") that are poorly filtered but are secreted into the lumen by organic anion transporters (OATs) in the proximal renal tubule. These are not effectively removed by conventional hemodialysis or peritoneal dialysis. Residual renal function, urine produced in patients with advanced renal failure or undergoing dialysis treatment, may represent, at least in part, secretion of fluid and uremic toxins, such as indoxyl sulfate, mediated by proximal tubule OATs and might serve as a useful survival function. In light of this new evidence of the physiological role of proximal tubule OATs, we suggest that measurement of renal tubular function and renal plasma flow may be of considerable value in understanding and managing chronic kidney disease. Data obtained in normal subjects indicate that renal plasma flow and renal tubular function might be measured by the clearance of the endogenous aryl amine, hippurate. Copyright © 2016 the American Physiological Society.

Prediction of the overall renal tubular secretion and hepatic clearance of anionic drugs and a renal drug-drug interaction involving organic anion transporter 3 in humans by in vitro uptake experiments.

Science.gov (United States)

Watanabe, Takao; Kusuhara, Hiroyuki; Watanabe, Tomoko; Debori, Yasuyuki; Maeda, Kazuya; Kondo, Tsunenori; Nakayama, Hideki; Horita, Shigeru; Ogilvie, Brian W; Parkinson, Andrew; Hu, Zhuohan; Sugiyama, Yuichi

2011-06-01

The present study investigated prediction of the overall renal tubular secretion and hepatic clearances of anionic drugs based on in vitro transport studies. The saturable uptake of eight drugs, most of which were OAT3 substrates (rosuvastatin, pravastatin, pitavastatin, valsartan, olmesartan, trichlormethiazide, p-aminohippurate, and benzylpenicillin) by freshly prepared human kidney slices underestimated the overall intrinsic clearance of the tubular secretion; therefore, a scaling factor of 10 was required for in vitro-in vivo extrapolation. We examined the effect of gemfibrozil and its metabolites, gemfibrozil glucuronide and the carboxylic metabolite, gemfibrozil M3, on pravastatin uptake by human kidney slices. The inhibition study using human kidney slices suggests that OAT3 plays a predominant role in the renal uptake of pravastatin. Comparison of unbound concentrations and K(i) values (1.5, 9.1, and 4.0 μM, for gemfibrozil, gemfibrozil glucuronide, and gemfibrozil M3, respectively) suggests that the mechanism of the interaction is due mainly to inhibition by gemfibrozil and gemfibrozil glucuronide. Furthermore, extrapolation of saturable uptake by cryopreserved human hepatocytes predicts clearance comparable with the observed hepatic clearance although fluvastatin and rosuvastatin required a scaling factor of 11 and 6.9, respectively. This study suggests that in vitro uptake assays using human kidney slices and hepatocytes provide a good prediction of the overall tubular secretion and hepatic clearances of anionic drugs and renal drug-drug interactions. It is also recommended that in vitro-in vivo extrapolation be performed in animals to obtain more reliable prediction.

Validation of a simple isotopic technique for the measurement of global and separated renal function

International Nuclear Information System (INIS)

Chachati, A.; Meyers, A.; Rigo, P.; Godon, J.P.

1986-01-01

Schlegel and Gates described an isotopic method for the measurement of global and separated glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) based on the determination by scintillation camera of the fraction of the injected dose (99mTc-DTPA-[ 131 I]hippuran) present in the kidneys 1-3 min after its administration. This method requires counting of the injected dose and attenuation correction, but no blood or urine sampling. We validated this technique by the simultaneous infusion of inulin and para-amino hippuric acid (PAH) in patients with various levels of renal function (anuric to normal). To better define individual renal function we studied 9 kidneys in patients either nephrectomized or with a nephrostomy enabling separated function measurement. A good correlation between inulin, PAH clearance, and isotopic GFR-ERPF measurement for both global and separate renal function was observed

Application of measuring 99mTc-MAG3 plasma clearance based on one-compartment model (MPC method) to pediatric patients

International Nuclear Information System (INIS)

Koizumi, Kiyoshi; Higashida, Kousuke; Arbab, A.S.; Toyama, Keiji; Arai, Takao; Yoshitomi, Tatsuya.

1997-01-01

Measurement of 99m Tc-MAG3 plasma clearance based on 1-compartment model (MPC method) were applied to 12 pediatric patients and evaluated for the factors which might affect the calculated results. Depth correction is a critical factor for the measurement of renal uptake. Three different equations for estimating renal depth were compared with the real depth measured by ultrasonography. The equation proposed by K. Itoh was suitable though the equations by T. Ito and Raynaud were insufficient. Estimation of distribution volume, which is regarded as circulating plasma volume (CPV), is also critical for the calculation of MAG3 clearance by MPC method. Precisely, hematocrit measured by venous sampling and circulating blood volume (CBV) calculated as 7.5% of body weight are used for estimation of CPV. However, assumed CPV as 5% of body weight was acceptable if the hematocrit was not severely deviated from the normal value. Simplified MPC method utilizing two factors mentioned above gave a positive correlation with Russell's one point sampling method. In conclusion, MPC method is applicable for pediatric patients. (author)

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

Quantitative arterial spin labelling perfusion measurements in rat models of renal transplantation and acute kidney injury at 3 T

Energy Technology Data Exchange (ETDEWEB)

Zimmer, Fabian; Schad, Lothar R.; Zoellner, Frank G. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine; Klotz, Sarah; Hoeger, Simone; Yard, Benito A.; Kraemer, Bernhard K. [Heidelberg Univ., Mannheim (Germany). Dept. of Medicine V

2017-05-01

To employ ASL for the measurement of renal cortical perfusion in particular renal disorders typically associated with graft loss and to investigate its potential to detect and differentiate the related functional deterioration i.e., in a setting of acute kidney injury (AKI) as well as in renal grafts showing acute and chronic transplant rejection. 14 Lewis rats with unilateral ischaemic AKI and 43 Lewis rats with renal grafts showing acute or chronic rejections were used. All ASL measurements in this study were performed on a 3 T MR scanner using a FAIR True-FISP approach to assess renal blood flow (RBF). Perfusion maps were calculated and the cortical blood flow was determined using a region-of-interest based analysis. RBF of healthy and AKI kidneys as well as of both rejection models, were compared. In a subsample of 20 rats, creatinine clearance was measured and correlated with cortical perfusion. RBF differs significantly between healthy and AKI kidneys (P < 0.001) with a mean difference of 213 ± 80 ml/100 g/min. Renal grafts with chronic rejections show a significantly higher (P < 0.001) mean cortical perfusion (346 ± 112 ml/100 g/min) than grafts with acute rejection (240 ± 66 ml/100 g/min). Both transplantation models have a significantly (P < 0.001) lower perfusion than healthy kidneys. Renal creatinine clearance is significantly correlated (R = 0.85, P < 0.001) with cortical blood flow. Perfusion measurements with ASL have the potential to become a valuable diagnostic tool, regarding the detection of renal impairment and the differentiation of disorders that lead to a loss of renal function and that are typically associated with graft loss.

Quantitative arterial spin labelling perfusion measurements in rat models of renal transplantation and acute kidney injury at 3 T

International Nuclear Information System (INIS)

Zimmer, Fabian; Schad, Lothar R.; Zoellner, Frank G.; Klotz, Sarah; Hoeger, Simone; Yard, Benito A.; Kraemer, Bernhard K.

2017-01-01

To employ ASL for the measurement of renal cortical perfusion in particular renal disorders typically associated with graft loss and to investigate its potential to detect and differentiate the related functional deterioration i.e., in a setting of acute kidney injury (AKI) as well as in renal grafts showing acute and chronic transplant rejection. 14 Lewis rats with unilateral ischaemic AKI and 43 Lewis rats with renal grafts showing acute or chronic rejections were used. All ASL measurements in this study were performed on a 3 T MR scanner using a FAIR True-FISP approach to assess renal blood flow (RBF). Perfusion maps were calculated and the cortical blood flow was determined using a region-of-interest based analysis. RBF of healthy and AKI kidneys as well as of both rejection models, were compared. In a subsample of 20 rats, creatinine clearance was measured and correlated with cortical perfusion. RBF differs significantly between healthy and AKI kidneys (P < 0.001) with a mean difference of 213 ± 80 ml/100 g/min. Renal grafts with chronic rejections show a significantly higher (P < 0.001) mean cortical perfusion (346 ± 112 ml/100 g/min) than grafts with acute rejection (240 ± 66 ml/100 g/min). Both transplantation models have a significantly (P < 0.001) lower perfusion than healthy kidneys. Renal creatinine clearance is significantly correlated (R = 0.85, P < 0.001) with cortical blood flow. Perfusion measurements with ASL have the potential to become a valuable diagnostic tool, regarding the detection of renal impairment and the differentiation of disorders that lead to a loss of renal function and that are typically associated with graft loss.

Late renal function after upper abdominal irradiation

International Nuclear Information System (INIS)

Morris, Monica M.; Willett, Christopher G.

1997-01-01

Purpose: This study assesses the late renal function and complications following upper abdominal irradiation. Methods and Materials: Eighty-six adult patients were identified who were treated with curative intent to the upper abdomen, received greater than 50% unilateral kidney irradiation to doses of at least 26 Gy, and survived for 1 year or more. Following treatment, the clinical course, blood pressure, addition of anti-hypertensive medications, serum creatinine and creatinine clearance were determined. Creatinine clearance was calculated by the formula: creatinine clearance equals [(140 - age) x (weight in kilograms)] / (72 x serum creatinine), which has a close correlation to creatinine clearances measured by 24 hour urine measurement. The percent change in creatinine clearance from pre-treatment values was analyzed. Mean follow-up was 6.7 years. Seventeen patients were followed for 11 or more years. Results: Of the 16 patients with pre-radiotherapy hypertension, eight required an increase in the number of medications for control and eight required no change in medication. Twenty-one patients developed hypertension in follow-up, 15 of whom required no medication. One patient developed malignant hypertension on the basis of renal artery stenosis. Acute or chronic renal failure was not observed in any patient. The serum creatinine for all 86 patients prior to irradiation was below 2 mg/100 ml; in follow-up it rose to between 2-3 mg/100 ml in five patients. On univariate analysis, older patient age, female sex, pre-existing hypertension and initially abnormal renal function (creatinine clearance <90mg/ml) were significantly correlated with later poor creatinine clearance (<50 mg/ml). Conclusions: After significant unilateral kidney irradiation, patients demonstrated a laboratory trend to increased creatinine and decreased creatinine clearance. With long-term follow-up, these physiologic changes did not appear to translate into a clinically relevant alteration in

Correlation between Creatinine Clearance and Transtubular Potassium Concentration Gradient in old people and chronic renal disease patients

International Nuclear Information System (INIS)

Musso, C.; Imperiali, N.; Algranati, L.; Miguel, R.D.; Liakopoulos, V.; Stefanidis, I.

2007-01-01

Senescence and chronic kidney disease (CKD) reduce progressively glomerular filtration rate (GFR) which usually results in an increase in potassium renal secretion. To evaluate whether the transtubular potassium concentration gradient (TTKG) is more accurate parameter for evaluating the renal secretion of this cation than using fractional excretion of potassium as its urinary secretion marker, we studied 55 subjects, 43 of them were healthy elderly volunteers and 12 were CKD patients. Exclusion criteria were: abnormal plasma potassium level or presence of any disease or drug that could induce alteration of balance of this electrolyte levels. All the subjects were on a diet with potassium content around 50 mmol/day. The curves, which demonstrate the relationship between creatinine clearance and TTKG and the grade of correlation between these two parameters were analyzed in both groups. We found that the transtubular potassium concentration gradient had a significant negative correlation with the creatinine clearance level in the healthy elderly group, while there was no correlation in the CKD group. (author)

Renal haemodynamics, sodium and water reabsorption during continuous intravenous infusion of recombinant interleukin-2

DEFF Research Database (Denmark)

Geertsen, P F; von der Maase, H; Olsen, Niels Vidiendal

1998-01-01

1. Renal haemodynamics, lithium and sodium clearance were measured in 14 patients treated with recombinant interleukin-2 for metastatic renal cell carcinoma. 2. Patients were studied before and after 72 h of continuous intravenous infusion of recombinant interleukin-2 (18x10(6) i.u..24 h-1.m-2) a...... effect. Changes in renal prostaglandin synthesis may contribute to the decrease in renal blood flow. The lithium clearance data suggest that an increased proximal tubular reabsorption rate may contribute to the decreased sodium clearance during recombinant interleukin-2 treatment....

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

Treatment of Moderate Sized Renal Pelvis Calculi: Stone Clearance Time Comparison of Extracorporeal Shock Wave Lithotripsy and Retrograde Intrarenal Surgery.

Science.gov (United States)

Ercil, Hakan; Alma, Ergun; Bas, Okan; Sener, Nevzat Can; Vuruskan, Ediz; Kuyucu, Faruk; Unal, Umut; Gören, Mehmet Resit; Evliyaoglu, Yalcin

2016-03-05

To compare the stone clearance times in patients undergoing extracorporeal shock wave lithotripsy (SWL) or retrograde intrarenal surgery (RIRS) for single radiopaque renal pelvis stones 10-20 mm in size. The results of this study may guide urologists and patients and aid in selecting the optimal preoperative treatment. Between January 2013 and February 2015, we conducted a retrospective study and collected data from 333 patients treated with SWL (n = 172) or RIRS (n = 161). We included successfully treated patients with a single radiopaque renal pelvis stone 10-20 mm in size to calculate stone clearance times. The average stone size for the SWL group was 14.62 ± 2.58 mm and 14.91 ± 2.92 mm for the RIRS group. The mean Hounsfield unit (HU) of the patients was 585.40 ± 158.39 HU in the SWL group and 567.74 ± 186.85 HU in the RIRS group. Following full fragmentation, the mean stone clearance time was 26.55 ± 9.71 days in the SWL group and 11.59 ± 7.01 days in the RIRS group (P < .001). One of the most overlooked parameters in urinary stone treatments is stone clearance. We believe this study will shed light for those who aim to conduct larger randomized prospective studies. .

Comparative study of conventional PAH and inulin clearance and slope clearance of 131I-o-hippuric acid and 51Cr-EDTA

International Nuclear Information System (INIS)

Berghaeuser, H.

1981-01-01

''Classic'' PAH and inulin clearance were determined in 81 patients with renal anomalies or renal diseases of different genesis and severity. In addition, radioisotope nephrography was carried out after administration of I-131-o-hippuric acid, followed by administration of Cr-51-EDTA. The activity decrease was recorded by a sensor located over the patient's right shoulder; the activities of a serum sample and of the urine excreted after 21 or 31 min were measured, and the findings were compared with those of the classic method. The clearance data calculated on the basis of the soulder measurements were hardly compatible with those of the conventional method in the case of 131 I-o-hippuric acid (r=0.54) and totally incompatible in the case of 51 Cr-EDTA. This means that the method described by Oberhausen is the only accurate method available for a quantitative assessment of the renal function on the basis of measurements of the activity decrease in the body. The activity of urine excreted after 31 min ( 131 I-hippuric acid:r=0.992, 51 Cr-EDTA:r=0.79) is a sufficiently accurate parameter although it is inaccurate at PAH clearance, values > 130 ml/min and inulin clearance values > 30 ml/min. Of the many parameters of radioisotope nephrogram curves, in the case of 131 I-o-hippuric acid only the parameters related to the ascent between 48 and 120 sec or to the secant ascent yield sufficient quantitative information for certain functional regions (r=0.9 resp. r=0.93). In the case of 51 Cr-EDTA, semiquantitative information on the renal function can be obtained by constructing secants on the nephrogram curves (r=0.7 resp. r=0.72). Here as in the case of 131 I-hippuric acid, the contribution of each kidney can be determined individually from the functional analysis of both kidneys. (orig.) [de

Dependence of 'CT clearance' on dosage and time

International Nuclear Information System (INIS)

Kaltenborn, H.A.; Klose, K.J.; Dexheimer, C.; Steinijans, V.

1989-01-01

The contrast medium dose used in CT renal function analysis corresponds to about 1 ml/kg body weight at a measurement interval of 5 or 10 minutes. In the present study the dependence of 'CT clearance' on dosage and time was examined in 12 healthy subjects. The amount of clearance was directly proportional to the employed contrast medium dose and to the length of the measurement interval. On account of the superior signal-to-noise ratio, the higher dose (1 ml/kg body weight) will continue to be prefered in future. The measurement interval can be limited to 10 minutes. (orig.) [de

The description of a method for accurately estimating creatinine clearance in acute kidney injury.

Science.gov (United States)

Mellas, John

2016-05-01

Acute kidney injury (AKI) is a common and serious condition encountered in hospitalized patients. The severity of kidney injury is defined by the RIFLE, AKIN, and KDIGO criteria which attempt to establish the degree of renal impairment. The KDIGO guidelines state that the creatinine clearance should be measured whenever possible in AKI and that the serum creatinine concentration and creatinine clearance remain the best clinical indicators of renal function. Neither the RIFLE, AKIN, nor KDIGO criteria estimate actual creatinine clearance. Furthermore there are no accepted methods for accurately estimating creatinine clearance (K) in AKI. The present study describes a unique method for estimating K in AKI using urine creatinine excretion over an established time interval (E), an estimate of creatinine production over the same time interval (P), and the estimated static glomerular filtration rate (sGFR), at time zero, utilizing the CKD-EPI formula. Using these variables estimated creatinine clearance (Ke)=E/P * sGFR. The method was tested for validity using simulated patients where actual creatinine clearance (Ka) was compared to Ke in several patients, both male and female, and of various ages, body weights, and degrees of renal impairment. These measurements were made at several serum creatinine concentrations in an attempt to determine the accuracy of this method in the non-steady state. In addition E/P and Ke was calculated in hospitalized patients, with AKI, and seen in nephrology consultation by the author. In these patients the accuracy of the method was determined by looking at the following metrics; E/P>1, E/P1 and 0.907 (0.841, 0.973) for 0.95 ml/min accurately predicted the ability to terminate renal replacement therapy in AKI. Include the need to measure urine volume accurately. Furthermore the precision of the method requires accurate estimates of sGFR, while a reasonable measure of P is crucial to estimating Ke. The present study provides the

Pregnancy Increases the Renal Secretion of N1-methylnicotinamide, an Endogenous Probe for Renal Cation Transporters, in Patients Prescribed Metformin.

Science.gov (United States)

Bergagnini-Kolev, Mackenzie C; Hebert, Mary F; Easterling, Thomas R; Lin, Yvonne S

2017-03-01

N 1 -methylnicotinamide (1-NMN) has been investigated as an endogenous probe for the renal transporter activity of organic cation transporter 2 (OCT2) and multidrug and toxin extrusion proteins 1 and 2-K (MATE1 and MATE2-K). As pregnancy increased the renal secretion of metformin, a substrate for OCT2, MATE1, and MATE2-K, we hypothesized that the renal secretion of 1-NMN would be similarly affected. Blood and urine samples collected from women prescribed metformin for type 2 diabetes, gestational diabetes, and polycystic ovarian syndrome during early, mid, and late pregnancy ( n = 34 visits) and postpartum ( n = 14 visits) were analyzed for 1-NMN using liquid chromatography-mass spectrometry. The renal clearance and secretion clearance, using creatinine clearance to correct for glomerular filtration, were estimated for 1-NMN and correlated with metformin renal clearance. 1-NMN renal clearance was higher in both mid (504 ± 293 ml/min, P pregnancy (557 ± 305 ml/min, P pregnancy (269± 267, P pregnancy compared with postpartum (342 ± 283 versus 76 ± 92 ml/min, P Metformin renal clearance and 1-NMN renal clearance were positively correlated (r s = 0.68, P pregnancy due to increased glomerular filtration and net secretion by renal transporters. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Uptake and washout of I-123-MIBG in neuronal and non-neuronal sites in rat hearts. Relationship to renal clearance

International Nuclear Information System (INIS)

Arbab, A.S.; Koizumi, Kiyoshi; Araki, Tsutomu

1996-01-01

We investigated the uptake and washout of I-123-metaiodobenzylguanidine (MIBG) in neuronal (both intra-and extravesicular) and non-neuronal sites in the heart and its relationship to renal clearance. Acute renal failure was induced in rats by ligating the renal vessels, and the findings were compared with those of sham-operated rats. Each group consisted of control, reserpine-treated and 6-hydroxydopamine (6-OHDA)-treated subgroups. Rats were sacrificed at 10 minutes and 4 hours after injection of MIBG. MIBG activity was calculated in specimens of heart, spleen, lung and blood. At 10 minutes, no significant difference in MIBG uptake in the heart was observed among the subgroups or between sham-operated and renal failure rats despite a significantly higher blood MIBG activity in the latter. At 4 hours, however, the hearts of both reserpine-treated and 6-OHDA-treated rats showed significantly lower MIBG uptake than control rats. Furthermore, the hearts of renal failure rats showed higher MIBG uptake in the control and reserpine-treated rats than in the corresponding subgroups in sham-operated rats. Intra and extravesicular neuronal uptake of MIBG in the heart were estimated using control, reserpine-treated and 6-OHDA-treated rats. Vesicular uptake values were similar in both the sham-operated group (0.51% ID/g) and the renal failure group (0.44% ID/g). But extravesicular neuronal uptake values were quite different in the renal failure group (0.86% ID/g) and the sham-operated group (0.19% ID/g). In conclusion, uptake to and washout from extravesicular neuronal sites may depend on the concentration of MIBG in the blood or the state of renal clearance, but vesicular uptake may be independent of these factors. (author)

Dynamic 18F-fluoride small animal PET to noninvasively assess renal function in rats

International Nuclear Information System (INIS)

Schnoeckel, Uta; Stegger, Lars; Schaefers, Klaus P.; Hermann, Sven; Schober, Otmar; Schaefers, Michael; Reuter, Stefan; Schlatter, Eberhard; Gabriels, Gert

2008-01-01

Renal function can be quantified by both laboratory and scintigraphic methods. In the case of small animal diagnostics, scintigraphic image-based methods are ideal since they can assess split renal function, work noninvasively, and can be repeated. The aim of this study is to validate a 18 F-PET-based method to quantify renal function in rats. Fluoride clearance was calculated from a dynamic whole body listmode acquisition of 60 min length in a small animal PET scanner following an i.v. injection of 15 MBq 18 F-fluoride. Volumes of interest (VOIs) were placed in the left ventricle and the bladder as well as traced around the kidney contours. The respective time-activity curves (TAC) were calculated. The renal 18 F-clearance was calculated by the ratio of the total renal excreted activity (bladder VOI) and the integral of the blood TAC. PET-derived renal function was validated by intraindividual measurements of creatinine clearance (n=23), urea clearance (n=23), and tubular excretion rate (TER-MAG3). The split renal function was derived from the injection of the clinically available radionuclide 99m Tc-mercaptotriglycine by blood sampling and planar renography (n=8). In all animals studied, PET revealed high-quality TACs. PET-derived renal fluoride clearance was linearly correlated with intraindividual laboratory measures (PET vs. creatinine: r=0.78; PET vs. urea: r=0.73; PET vs. TER-MAG3: r=0.73). Split function was comparable ( 18 F-PET vs. MAG3-renography: r=0.98). PET-derived measures were highly reproducible. 18 F-PET is able to noninvasively assess renal function in rats and provides a significant potential for serial studies in different experimental scenarios. (orig.)

A camera based calculation of 99m Tc-MAG-3 clearance using conjugate views method

International Nuclear Information System (INIS)

Hojabr, M.; Rajabi, H.; Eftekhari, M.

2004-01-01

Background: measurement of absolute or different renal function using radiotracers plays an important role in the clinical management of various renal diseases. Gamma camera quantitative methods is approximations of renal clearance may potentially be as accurate as plasma clearance methods. However some critical factors such as kidney depth and background counts are still troublesome in the use of this technique. In this study the conjugate-view method along with some background correction technique have been used for the measurement of renal activity in 99m Tc- MAG 3 renography. Transmission data were used for attenuation correction and the source volume was considered for accurate background subtraction. Materials and methods: the study was performed in 35 adult patients referred to our department for conventional renography and ERPF calculation. Depending on patients weight approximately 10-15 mCi 99 Tc-MAG 3 was injected in the form of a sharp bolus and 60 frames of 1 second followed by 174 frames of 10 seconds were acquired for each patient. Imaging was performed on a dual-head gamma camera(SOLUS; SunSpark10, ADAC Laboratories, Milpitas, CA) anterior and posterior views were acquired simultaneously. A LEHR collimator was used to correct the scatter for the emission and transmission images. Buijs factor was applied on background counts before background correction (Rutland-Patlak equation). gamma camera clearance was calculated using renal uptake in 1-2, 1.5-2.5, 2-3 min. The same procedure was repeated for both renograms obtained from posterior projection and conjugated views. The plasma clearance was also directly calculated by three blood samples obtained at 40, 80, 120 min after injection. Results: 99 Tc-MAG 3 clearance using direct sampling method were used as reference values and compared to the results obtained from the renograms. The maximum correlation was found between conjugate view clearance at 2-3 min (R=0.99, R 2 =0.98, SE=15). Conventional

Dynamic {sup 18}F-fluoride small animal PET to noninvasively assess renal function in rats

Energy Technology Data Exchange (ETDEWEB)

Schnoeckel, Uta; Stegger, Lars; Schaefers, Klaus P.; Hermann, Sven; Schober, Otmar; Schaefers, Michael [Klinik und Poliklinik fuer Nuklearmedizin, Muenster (Germany); Reuter, Stefan; Schlatter, Eberhard; Gabriels, Gert [Universitaetsklinikum Muenster, Medizinische Klinik und Poliklinik D, Experimentelle Nephrologie, Muenster (Germany)

2008-12-15

Renal function can be quantified by both laboratory and scintigraphic methods. In the case of small animal diagnostics, scintigraphic image-based methods are ideal since they can assess split renal function, work noninvasively, and can be repeated. The aim of this study is to validate a {sup 18}F-PET-based method to quantify renal function in rats. Fluoride clearance was calculated from a dynamic whole body listmode acquisition of 60 min length in a small animal PET scanner following an i.v. injection of 15 MBq {sup 18}F-fluoride. Volumes of interest (VOIs) were placed in the left ventricle and the bladder as well as traced around the kidney contours. The respective time-activity curves (TAC) were calculated. The renal {sup 18}F-clearance was calculated by the ratio of the total renal excreted activity (bladder VOI) and the integral of the blood TAC. PET-derived renal function was validated by intraindividual measurements of creatinine clearance (n=23), urea clearance (n=23), and tubular excretion rate (TER-MAG3). The split renal function was derived from the injection of the clinically available radionuclide {sup 99m}Tc-mercaptotriglycine by blood sampling and planar renography (n=8). In all animals studied, PET revealed high-quality TACs. PET-derived renal fluoride clearance was linearly correlated with intraindividual laboratory measures (PET vs. creatinine: r=0.78; PET vs. urea: r=0.73; PET vs. TER-MAG3: r=0.73). Split function was comparable ({sup 18}F-PET vs. MAG3-renography: r=0.98). PET-derived measures were highly reproducible. {sup 18}F-PET is able to noninvasively assess renal function in rats and provides a significant potential for serial studies in different experimental scenarios. (orig.)

The influence of body posture on lithium clearance

DEFF Research Database (Denmark)

Kamper, A L; Strandgaard, S; Holstein-Rathlou, N H

1988-01-01

measured four times at 1-week intervals: two in the supine and one in the sitting position, and one when the subject was walking around. Glomerular filtration rate was not influenced by posture changes. On the contrary, lithium clearance, which in the supine position was 30 +/- 9 ml/min (1 SD), tended...... during moderate physical activity. Hence, when renal tubular function is studied with the lithium clearance method, standardization of posture and physical activity is important. In such studies physical activity such as walking should particularly be avoided....

Comparison of glomerular filtration rates by dynamic renal scintigraphy and dual-plasma sample clearance method in diabetic nephropathy

International Nuclear Information System (INIS)

Xie Peng; Huang Jianmin; Pan Liping; Liu Xiaomei; Wei Lingge; Gao Jianqing

2010-01-01

Objective: To evaluate the accuracy of renal scintigraphy for the estimation of glomerular filtration rates (dGFR) in patients with diabetic nephropathy as compared to the conventional dual-plasma sample clearance method (pscGFR). Methods: Forty-six patients with diabetic nephropathy underwent both dynamic renal scintigraphy and dual-plasma sample measurement after 99 Tc m -DTPA injection. Paired student t-test and correlation analysis were performed to compare dGFR and pscGFR (normalized to body surface area, 1.73 m -2 ). Results: The mean dGFR was higher than mean pscGFR ((51.08±26.78)ml·min -1 vs (44.06±29.43)ml·min -1 , t=4.209, P=0.000). The dGFR correlated with pscGFR (r=0.923, P=0.000) linearly (regression equation: pscGFR=1.015 x dGFR -7.773, F=254.656, P=0.000). Conclusions: dGFR correlated well with pscGFR. Although it could not absolutely replace the latter in patients with diabetic nephropathy, dGFR could reasonably evaluate the filtration function for these patients. (authors)

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

Kidney function measured by clearance. Methods and indications. An update; Zur Messung der Nierenfunktion durch Clearancebestimmungen. Methoden und Indikationen. Ein Update

Energy Technology Data Exchange (ETDEWEB)

Durand, E. [Universitaetskrankenhaus Bicetre, Paris (France); Mueller-Suur, R. [Karolinska Inst., Danderyds Krankenhaus und Aleris Fysiologlab, Stockholm (Sweden)

2010-09-15

Renal function impairment can be monitored by many tests. Measurement of plasma-creatinine level is the most used method, 24 h plasma-creatininclearance with urine collection is used by others and also other alternative but indirect methods exist. However, the use of radionuclide-clearances is by far the easiest performed method with the highest accuracy and precision and gives very low irradiation dose. In the following we will discuss the different radiopharmaceuticals in use, their plus and minus, the different clearance methods in use, their limitations and give some clinically important indications to perform clearance investigations according to consensus reports. Summarizing the use of plasma clearance of 51-Cr-EDTA after a single injection with one blood sample can be generally recommended, however with some modifications in special clinical situations, which are pointed out. Please note, that this paper is, for a significant part, an update of a previous paper published 2003 in ''Der Nuklearmediziner'' (orig.)

Utility of radioisotopic filtration markers in chronic renal insufficiency: Simultaneous comparison of 125I-iothalamate, 169Yb-DTPA, 99mTc-DTPA, and inulin. The Modification of Diet in Renal Disease Study

International Nuclear Information System (INIS)

Perrone, R.D.; Steinman, T.I.; Beck, G.J.; Skibinski, C.I.; Royal, H.D.; Lawlor, M.; Hunsicker, L.G.

1990-01-01

Assessment of glomerular filtration rate (GFR) with inulin is cumbersome and time-consuming. Radioisotopic filtration markers have been studied as filtration markers because they can be used without continuous intravenous (IV) infusion and because analysis is relatively simple. Although the clearances of 99mTc-DTPA, 169Yb-DTPA, and 125I-iothalamate have each been compared with inulin, rarely has the comparability of radioisotopic filtration markers been directly evaluated in the same subject. To this purpose, we determined the renal clearance of inulin administered by continuous infusion and the above radioisotopic filtration markers administered as bolus injections, simultaneously in four subjects with normal renal function and 16 subjects with renal insufficiency. Subjects were studied twice in order to assess within-study and between-study variability. Unlabeled iothalamate was infused during the second half of each study to assess its effect on clearances. We found that renal clearance of 125I-iothalamate and 169Yb-DTPA significantly exceeded clearance of inulin in patients with renal insufficiency, but only by several mL.min-1.1.73m-2. Overestimation of inulin clearance by radioisotopic filtration markers was found in all normal subjects. No differences between markers were found in the coefficient of variation of clearances either between periods on a given study day (within-day variability) or between the two study days (between-day variability). The true test variability between days did not correlate with within-test variability. We conclude that the renal clearance of 99mTc-DTPA, 169Yb-DTPA, or 125I-iothalamate administered as a single IV or subcutaneous injection can be used to accurately measure GFR in subjects with renal insufficiency; use of the single injection technique may overestimate GFR in normal subjects

Monoexponential analysis of plasma disappearance of 99mTc-DTPA and 131I-iodohippurate: A reliable method for measuring changes of renal function

International Nuclear Information System (INIS)

Clifton, G.G.; Anderson, C.; McMahon, G.; Vargas, R.; Wallin, J.D.

1989-01-01

Glomerular filtration rate and effective renal plasma flow were measured in 170 subjects using monoexponential analysis of plasma disappearance curves for 99m Tc-DTPA and 131 I-iodohippurate after single injection. In the current study population, glomerular filtration rate and effective renal plasma flow decreased with increasing age, were less in females than in males, and were less in hypertensives than in normotensives. Differences in glomerular filtration rate according to age and sex in the current study were similar to those reported using traditional creatinine clearance methodology. Monoexponential treatment of plasma isotope disappearance gave reproducible values for both glomerular filtration rate and effective renal plasma flow when measured either during the day or on a daily basis. Intraindividual coefficient of variation was less than 10% for both 99m Tc-DTPA and 131 I-iodohippurate clearances derived from monoexponential analysis. These results demonstrate that monoexponential analysis of plasma disappearance curves for 99m Tc-DTPA and 131 I-iodohippurate after a single injection is a useful method for evaluating changes in renal hemodynamics either during chronic drug therapy or acutely after single dose administration

Bumetanide kinetics in renal failure

International Nuclear Information System (INIS)

Pentikaeinen, P.J.P.; Pasternack, A.; Lampainen, E.; Neuvonen, P.J.; Penttilae, A.

1985-01-01

To study the effects of renal failure on bumetanide kinetics, the authors administered single intravenous doses of 1.0 mg/3.08 microCi 14 C-bumetanide to six healthy subjects and 22 patients with variable degrees of renal failure. The kinetics of 14 C-bumetanide and total 14 C were adequately described by a two-compartment open model in the control subjects and in the patients. The volume of the central compartment and the distribution t1/2 were of the same order in both groups, whereas the mean (+/- SE) volume at steady state was larger (22.1 +/- 1.6 and 16.9 +/- 1.0 L) and the elimination t1/2 was longer (1.9 +/- 0.2 and 1.4 +/- 0.1 hours) in patients with renal failure than in healthy controls. Bumetanide renal clearance was lower (10 +/- 3 and 90 +/- 13 ml/min) in patients than in subjects and correlated with creatinine clearance (r = 0.784) and log serum creatinine level (r = -0.843), whereas nonrenal clearance was significantly higher in the patients (153 +/- 14 and 99 +/- 6 ml/min). Bumetanide total plasma clearance did not significantly change. The non-protein-bound, free fraction of bumetanide was higher in patients and correlated with plasma albumin levels (r = -0.777). The kinetics of total 14 C showed similar but greater changes than those of 14C-bumetanide. Thus the most important changes in bumetanide kinetics in patients with renal failure are low renal clearance and a high free fraction, with a consequent increase in nonrenal clearance, volume of distribution, and elimination t1/2

A simple estimation of the renal plasma flow

International Nuclear Information System (INIS)

Shinpo, Takako

1987-01-01

The renal plasma flow was determined conventionally by the excretive ratio to urine using a 131 I-Hippuran renogram. In this report, we proposed the renal clearance, the product of the disappearance rate coefficient and the maximum counts of the bladder, for the simple quantitative value of renal plasma flow. The disappearance rate coefficient was calculated by approximating the exponential function of the initial slope from the disappearance curve of the heart. The renal clearances was compared with the renal plasma flow calculated by the conventional method. The results gave a high correlation coefficient of r = 0.91. The renal clearances can be calculated easily and it offers useful renogram information. (author)

Investigations of renal clearance in nuclear medicine

International Nuclear Information System (INIS)

Oberhausen, E.

1981-01-01

Comparative investigations of PAH- and inulin-clearance and results of investigations with J-131-hippurate and Cr-51-EDTA, which were performed by a partly screened whole body counter including measurements of activity retention of blood samples, are showing good correlation. If the radio-isotope nephrography is worked out together with the decreased retention curve, separate results of the function of both kidneys can be given. Modifications which were tried to analyze a small part of the retention curve instead of the whole body are inaccurate, if they are below 300 ml/min. (orig.) [de

Arterio-venous concentration difference of [51Cr]EDTA after a single injection in man. Significance of renal function and local blood flow

DEFF Research Database (Denmark)

Rehling, M; Hyldstrup, L; Henriksen, Jens Henrik Sahl

1989-01-01

, whereas the difference was very sensitive to even small changes in forearm blood flow within the physiological range. For measurement of renal plasma clearance it is recommended to use one long period: from the time of injection until 300 min p.i. or longer. If the clearance period is too short, the use...... introduced in the measurement of renal plasma clearance and total plasma clearance by using venous blood samples instead of arterial. In 13 patients with GFR ranging from 29 to 150 ml min-1, Ca was higher than Cv immediately after the injection. After mean 38 min (range 12-82 min) the two curves crossed...... of venous samples will overestimate the true renal clearance. Plasma clearance determined by venous and arterial blood samples does not differ significantly as long as the concentration is followed from the time of injection and a long period is applied. When simplified plasma clearance techniques are used...

Intercalibration of mussel Mytilus edulis clearance rate measurements

NARCIS (Netherlands)

Kjerulf Petersen, J.; Bougrier, S.; Smaal, A.C.; Garen, P.; Robert, S.; Larsen, J.E.N.; Brummelhuis, E.B.M.

2004-01-01

Clearance rate (CR) was measured in blue mussels Mytilus edulis L. from Aiguillon Bay and the Oosterschelde using 3 different methods: the flow-through method, the bio-deposition method and the indirect or clearance method. CR differed significantly as a function of the method used and of the origin

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.

Prognosis for recovery of function in acute renal failure

International Nuclear Information System (INIS)

Harwood, T.H. Jr.; Hiesterman, D.R.; Robinson, R.G.; Cross, D.E.; Whittier, F.C.; Diederich, D.A.; Grantham, J.J.

1976-01-01

Twenty-four survivors of acute, nonobstructive, nonnephritic renal failure had a renal scan using iodohippurate sodium I 131 performed early in the acute illness. Scans were judged according to whether the renal images were prominent, faint, or absent during the first 30 minutes after intravenous injection of 100 to 250 microcuries of iodohippurate sodium I 131. All ten patients with prominent renal images attained life-sustaining renal function with an average postrecovery creatinine clearance of 80 ml/min. Of the seven patients with faint renal images, six recovered life-sustaining renal function (average creatinine clearance of 39 ml/min), and one required chronic hemodialysis. Seven patients had no renal image initially; four recovered life-sustaining renal function with an average creatinine clearance of 25 ml/min; three required chronic hemodialysis. We conclude that, for patients with acute renal failure, the appearance of the renal image obtained using this substance is an important indicator of renal viability and of the likelihood for functional recovery

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)

Renal effects of amino acids and dopamine in renal transplant recipients treated with or without cyclosporin A

DEFF Research Database (Denmark)

Hansen, J M; Olsen, Niels Vidiendal; Leyssac, P P

1996-01-01

1. The nephrotoxic effects of cyclosporin A may diminish the ability of the transplanted kidney to increase the glomerular filtration rate and effective renal plasma flow during infusion of dopamine or amino acids. 2. The present study included 16 renal transplant recipients transplanted for more...... and of dopamine in renal transplant recipients with a good graft function.......-creatinine, 89 +/- 6 mumol/l). The renal response to infusion of dopamine and of amino acids was investigated on two separate days. All clearance measurements were carried out at nadir cyclosporin A blood levels. 3. Effective renal plasma flow increased significantly in the non-cyclosporin A group...

Prediction of differential creatinine clearance in chronically obstructed kidneys by non-contrast helical computerized tomography

International Nuclear Information System (INIS)

Ng, Cheuk Fan; Chan, L.W.; Cheng, C.W.; Yu, S.C.H.; Wong, W.S.; Wong, K.T.

2004-01-01

Purpose: We investigate the use of non-contrast helical computerized tomography (NCHCT) in the measurement of differential renal parenchymal volume as a surrogate for differential creatinine clearance (Cr Cl) for unilateral chronically obstructed kidney. Materials And Methods: Patients with unilateral chronically obstructed kidneys with normal contralateral kidneys were enrolled. Ultrasonography (USG) of the kidneys was first done with the cortical thickness of the site with the most renal substance in the upper pole, mid-kidney, and lower pole of both kidneys were measured, and the mean cortical thickness of each kidney was calculated. NCHCT was subsequently performed for each patient. The CT images were individually reviewed with the area of renal parenchyma measured for each kidney. Then the volume of the slices was summated to give the renal parenchymal volume of both the obstructed and normal kidneys. Finally, a percutaneous nephrostomy (PCN) was inserted to the obstructed kidney, and Cr Cl of both the obstructed kidney (PCN urine) and the normal side (voided urine) were measured two 2 after the relief of obstruction. Results: From March 1999 to February 2001, thirty patients were enrolled into the study. Ninety percent of them had ureteral calculi. The differential Cr Cl of the obstructed kidney (%CrCl) was defined as the percentage of Cr Cl of the obstructed kidney as of the total Cr Cl, measured 2 weeks after relief of obstruction. The differential renal parenchymal volume of the obstructed kidney (%CTvol) was the percentage of renal parenchymal volume as of the total parenchymal volume. The differential USG cortical thickness of the obstructed kidney (%USGcort) was the percentage of mean cortical thickness as of the total mean cortical thickness. The Pearson's correlation coefficient (r) between %CTvol and %CrCl and that between %USGcort and %CrCl were 0.756 and 0.543 respectively. The regression line was %CrCl = (1.00) x %CTvol - 14.27. The %CTvol

Prediction of differential creatinine clearance in chronically obstructed kidneys by non-contrast helical computerized tomography

Directory of Open Access Journals (Sweden)

Ng C.F.

2004-01-01

Full Text Available PURPOSE: We investigate the use of non-contrast helical computerized tomography (NCHCT in the measurement of differential renal parenchymal volume as a surrogate for differential creatinine clearance (CrCl for unilateral chronically obstructed kidney. MATERIALS AND METHODS: Patients with unilateral chronically obstructed kidneys with normal contralateral kidneys were enrolled. Ultrasonography (USG of the kidneys was first done with the cortical thickness of the site with the most renal substance in the upper pole, mid-kidney, and lower pole of both kidneys were measured, and the mean cortical thickness of each kidney was calculated. NCHCT was subsequently performed for each patient. The CT images were individually reviewed with the area of renal parenchyma measured for each kidney. Then the volume of the slices was summated to give the renal parenchymal volume of both the obstructed and normal kidneys. Finally, a percutaneous nephrostomy (PCN was inserted to the obstructed kidney, and CrCl of both the obstructed kidney (PCN urine and the normal side (voided urine were measured two 2 after the relief of obstruction. RESULTS: From March 1999 to February 2001, thirty patients were enrolled into the study. Ninety percent of them had ureteral calculi. The differential CrCl of the obstructed kidney (%CrCl was defined as the percentage of CrCl of the obstructed kidney as of the total CrCl, measured 2 weeks after relief of obstruction. The differential renal parenchymal volume of the obstructed kidney (%CTvol was the percentage of renal parenchymal volume as of the total parenchymal volume. The differential USG cortical thickness of the obstructed kidney (%USGcort was the percentage of mean cortical thickness as of the total mean cortical thickness. The Pearson's correlation coefficient (r between %CTvol and %CrCl and that between %USGcort and %CrCl were 0.756 and 0.543 respectively. The regression line was %CrCl = (1.00 x %CTvol - 14.27. The %CTvol

Single-sample 99mTc-diethylenetriamine penta-acetate plasma clearance in advanced renal failure by the mean sojourn time approach.

Science.gov (United States)

Gref, Margareta C; Karp, Kjell H

2009-03-01

The single-sample Tc-diethylenetriamine penta-acetate (DTPA) clearance method by Christensen and Groth is recommended by the Radionuclides in Nephrourology Committee on Renal Clearance for use in adults with an estimated glomerular filtration rate (GFR) > or = 30 ml/min. The purpose of this study was to test a new Tc-DTPA single-sample low clearance formula for GFR lesser than 30 ml/min. Twenty-one adult patients (29 investigations) were included. Reference clearance was calculated with both Cr-EDTA and Tc-DTPA according to Brøchner-Mortensen with samples drawn between 3 and 24 h. Single-sample clearance was calculated from a 24 h sample using the low clearance formula(Equation is included in full-text article.) C(t) is the activity of the tracer in the plasma sample t minutes after the injection and Q0 is the injected amount. ECV is the extracellular volume in ml defined as the distribution volume of the tracer. ECV is estimated from the body surface area as ECV=8116.6xbody surface area-28.2. The mean difference between reference and Tc-DTPA single-sample clearance was -0.5 ml/min (SD 1.0 ml/min) for Tc-DTPA and -0.8 ml/min (SD 1.2 ml/min) for Cr-EDTA as reference clearance. In adult patients it is possible, even with GFR lesser than 30 ml/min, to get an accurate determination of Tc-DTPA plasma clearance from a single sample using the mean sojourn time approach. The blood sample should be obtained about 24 h after injection of the GFR tracer.

Extension of the Calvert formula to patients with severe renal insufficiency.

Science.gov (United States)

Oguri, Tomoyo; Shimokata, Tomoya; Ito, Isao; Yasuda, Yoshinari; Sassa, Naoto; Nishiyama, Masami; Hamada, Akinobu; Hasegawa, Yoshinori; Ando, Yuichi

2015-07-01

The Calvert formula was derived from the study among patients with glomerular filtration rates (GFRs) of 33-135 ml/min, and it remains unclear whether the formula can be used to calculate optimal and safe dosages of carboplatin in patients with severe renal insufficiency. We evaluated the utility of this formula in patients with severe renal insufficiency. For pharmacokinetic analysis, we studied nine adult Japanese patients with advanced cancer who had an estimated GFR of lower than 30 ml/min/1.73 m(2), as calculated by the Japanese equation for estimating GFR, or who were receiving hemodialysis. The dose of carboplatin was calculated with the Calvert formula, in which GFR was measured by inulin clearance or was assumed to be 0 in patients requiring hemodialysis. Hemodialysis was started 23 h after the end of carboplatin infusion. Although there was a significant correlation between the estimated and measured carboplatin clearance, the estimated clearance was consistently higher than the measured clearance [mean prediction error ± standard deviation = 41.0 ± 26.3 %] in all seven patients with renal insufficiency (GFR, median 21.4, range 7.8-31.4 ml/min) and in the two hemodialysis patients. Actual areas under the concentration-time curve (AUC) (mg/ml min) were 5.4, 5.7, 6.2, and 9.0 for the four patients with a target AUC (mg/ml min) of 5; 5.7, 6.2, and 7.1 for the three patients with a target AUC (mg/ml min) of 4; and 5.1 and 8.7 for the two hemodialysis patients with a target AUC (mg/ml min) of 5. The measured clearance of carboplatin ranged from 23.0 to 51.3 ml/min in the seven patients not receiving hemodialysis. The pre-hemodialysis carboplatin clearance in the hemodialysis patients was 20.5 and 11.1 ml/min, respectively. For adult patients with severe renal insufficiency, the Calvert formula causes carboplatin overdosing by overestimating the carboplatin clearance.

The kidneys play a central role in the clearance of rhGH in rats

DEFF Research Database (Denmark)

Vestergaard, Bill; Thygesen, Peter; Kreilgaard, Mads

2016-01-01

at treatment of patients with growth hormone disorders. The purpose of this study was to investigate the relative importance of the kidneys in the clearance of rhGH. The study employed a newly validated nephrectomy rat model and a population based pharmacokinetic approach to assess renal clearance of rh...... that renal clearance plays a pivotal role in the elimination of rhGH in rats....

Production of plastic scintillation survey meter for clearance verification measurement

International Nuclear Information System (INIS)

Tachibana, Mitsuo; Shiraishi, Kunio; Ishigami, Tsutomu; Tomii, Hiroyuki

2008-03-01

In the Nuclear Science Research Institute, the decommissioning of various nuclear facilities is carried out according to the plan for meeting the midterm goal of the Japan Atomic Energy Agency (JAEA). An increase in the clearance verification measurement of concrete on buildings and the radiation measurement for releasing controlled areas will be expected along with the dismantlement of nuclear facilities in the future. The radiation measurement for releasing controlled areas has been carried out in small-scale nuclear facilities including the JPDR (Japan Power Demonstration Reactor). However, the radiation measurement with an existing measuring device was difficult in effects of radiation from radioactive materials that remains in buried piping. On the other hand, there is no experience that the clearance verification measurement is executed in the JAEA. The generation of a large amount of clearance object will be expected along with the decommissioning of the nuclear facilities in the future. The plastic scintillation survey meter (hereafter, 'PL measuring device') was produced to apply to the clearance verification measurement and the radiation measurement for releasing controlled areas. The basic characteristic test and the actual test were confirmed using the PL measuring device. As a result of these tests, it was found that the evaluation value of radioactivity with the PL measuring device was accuracy equal with the existing measuring device. The PL measuring device has feature of the existing measuring device with a light weight and easy operability. The PL measuring device can correct the gamma ray too. The PL measuring device is effective to the clearance verification measurement of concrete on buildings and the radiation measurement for releasing controlled areas. (author)

Applicability of Clearance Automatic Laser Inspection System to Clearance Measurement of Concrete Segments

International Nuclear Information System (INIS)

Sasaki, M.; Ogino, H.; Hattori, T.

2009-01-01

In the decommissioning of a nuclear power plant, large amounts of metal scrap and concrete segments require disposal when dismantling the nuclear reactor and surrounding facilities. When their activity level is negligible or sufficiently small, they can be regarded as general industrial waste. To distinguish between radioactive and nonradioactive materials, the clearance level for each radionuclide has been determined in units of activity concentration. These clearance levels are indicated in the International Atomic Energy Agency (IAEA) Safety Standards Series No. RS-G-1.7. The Japanese regulatory authority decided in 2005 to adopt the values given in RS-G-1.7 as clearance levels in legislation. Recently, a Clearance Automatic Laser Inspection System (CLALIS) has been developed utilizing gamma-ray measurement, automatic laser shape measurement and Monte Carlo calculation. CLALIS comprises four laser scanners and eight large plastic scintillation detectors surrounded by a 5-cm-thick lead shield. Using three-dimensional (3D) laser scanning, a measurement target, which is placed on the measuring tray, is represented as a dot image. The dot image is converted into voxels after noise removal, and is written in MCNP (A General Monte Carlo N-Particle Transport Code System) input files. When the gamma-ray measurement is carried out, the MCNP calculations are also carried out to obtain the calibration factor and background (BG) correction factors. For the clearance measurement of concrete segments, the effect of gamma-rays from natural radionuclides in the measurement target, such as K-40 and the radioactive decay products of Th-232 and U-238, should be taken into account to ensure adequate waste management. Since NE102A plastic scintillation detectors are used for gamma-ray measurement in CLALIS, it is impossible to distinguish between the count rates of natural radionuclides and contaminants on the basis of gamma-ray energy information. To overcome this problem, the

Metronidazole pharmacokinetics in patients with acute renal failure.

Science.gov (United States)

Somogyi, A A; Kong, C B; Gurr, F W; Sabto, J; Spicer, W J; McLean, A J

1984-02-01

The pharmacokinetics and metabolism of intravenous metronidazole were studied in six patients with acute renal failure. In two of the patients a single dose (500 mg) of metronidazole was administered, whereas in four patients the steady-state pharmacokinetics were studied after four days therapy of 500 mg twice daily. Plasma concentrations of metronidazole and its hydroxy and acetic acid metabolites were measured by a specific and sensitive HPLC method. The volume of distribution was 0.65 +/- 0.13 l/kg (mean +/- S.D.), elimination half-life was 9.9 +/- 2.5 h and total plasma clearance was 55.5 +/- 17.7 ml/min. Renal clearance was almost non-existent (1.4 +/- 1.4 ml/min), whereas non-renal clearance was 54.0 +/- 18.2 ml/min. Steady-state plasma concentrations of metronidazole were 15.3 +/- 3.8 mg/l, the hydroxy metabolite were 17.4 +/- 2.0 mg/l and the acetic acid metabolite were 1.2 +/- 0.8 mg/l. In the patients studied, a dosing regimen of 500 mg twice daily resulted in therapeutically adequate blood levels of metronidazole.

Frequency of stone clearance after extracorporeal shockwave ...

African Journals Online (AJOL)

Objective: To determine the rate of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for renal stones in adult patients with renal insufficiency. Subjects and methods: This is a cross-sectional descriptive study of 117 adult patients who underwent ESWL. The indications for ESWL were determined by the ...

RENAL INVOLVEMENT IN SUBJECTS WITH PERIPHERAL ATHEROSCLEROSIS

International Nuclear Information System (INIS)

FAWZY, A.; IBRAHIM, S.

2008-01-01

Ischemic nephropathy is an important cause of renal failure.Sub-clinical renal function abnormalities may exist in patients with extra renal atherosclerosis and may precede the onset of overt ischemic nephropathy. To assess the impact of extrarenal atherosclerosis on the kidney, the study evaluated renal function in 50 subjects with differing degrees of peripheral atherosclerosis without manifest clinical or laboratory signs of ischemic nephropathy and renovascular hypertension.All laboratory testing including total LDL and HDL-cholesterol, triglycerides, ultrasonography with Doppler analysis for the localization of peripheral vascular disease (carotid and lower limb arteries), and non-invasive evaluation of renal function by radionuclide studies of renal plasma flow (MAG3 clearance) and glomerular filtration (DTPA clearance) were determined as well as smoking habit was recorded. By combining sonographic data on arterial tree stenosis (ATS), the subjects were grouped according to the atherosclerotic vascular damage (ATS involvement). The results showed no change in plasma creatinine while DTPA clearance was increased from 91.58±26.53 to 93.47±24.82 ml/min/1.73 m. MAG3 clearance was progressively declined with the severity of vascular damage from 244.86 ± 60.60 to 173.59±58.74 ml/min/1.73 m.Stepwise, multiple regression analysis indicated that MAG3 clearance was best explained by ATS involvement (standardized B coefficient -0.40; P< 0.001), smoking habit (-0.34;P=0.004) and serum LDL-cholesterol (-0.24; P<0.035).It could be concluded that the renal hemodynamic profile in atherosclerotic patients might constitute functional evidence of the silent phase of ischemic renal disease. The findings suggest that renal function should be carefully assessed in patients with extrarenal atherosclerosis, particularly in those with classic cardiovascular risk factors

Rapid decline in 51Cr-EDTA measured renal function during the first weeks following lung transplantation

DEFF Research Database (Denmark)

Hornum, M.; Iversen, M.; Steffensen, I.

2009-01-01

We previously described a 54% decline in renal function at 6 months after lung transplantation (LTx). We hypothesized that this decline is a very early event following LTx. Thirty-one consecutive patients (16 females/15 males), mean age 49 (+/-13) years, with emphysema, cystic fibrosis/bronchiect......We previously described a 54% decline in renal function at 6 months after lung transplantation (LTx). We hypothesized that this decline is a very early event following LTx. Thirty-one consecutive patients (16 females/15 males), mean age 49 (+/-13) years, with emphysema, cystic fibrosis....../bronchiectasis or idiopathic pulmonary fibrosis were included in an analysis of renal function before and after LTx. The glomerular filtration rate (GFR) was measured using the (51)Cr-ethylenediaminetetra acetic acid plasma clearance single injection technique (mGFR) at baseline before transplantation and at 1, 2, 3 and 12...

Measurement of effective renal plasma flow in congestive heart failure

International Nuclear Information System (INIS)

Tauxe, W.N.; Dubovsky, E.V.; Mantle, J.A.; Dustan, H.P.; Logic, J.R.

1981-01-01

In the management of patients with congestive heart failure (CHF), it is often desirable to have precise knowledge of overall renal function, including the effective renal plasma flow (ERPF). It has long been recognized that ERPF is diminished in CHF. Since glomerular filtration rate is often decreased to a much lesser extent, other noninvasive procedures such as the measurement of creatinine clearances may not be entirely suitable. ERPF determination by the single plasma sampling (SPS) method affords a rapid, simple, noninvasive, and economical technique that is quite accurate and reproducible. A SPS method has been well-tested in patients following renal transplantation plus a wide variety of nephrological disorders. We have been concerned whether the SPS method would be valid in volume expanded patients. In 28 determinations of ERPF in patients with CHF, and in five patients who did not have CHF, we have found the SPS estimation of ERPF to yield results that are not clinically significantly different from those obtained by the detailed compartmental analysis method. The volumes of 131 I-orthoiodohippurate (OIH) distribution were found to be somewhat higher in CHF than in controls, but fractional rate constants were proportionately lower so that intercompartmental flow rates and OIH concentrations were not different from controls. Therefore, the SPS estimation of ERPF is valid in patients with CHF and may be useful in monitoring the renal effects of various hemodynamic and pharmacological interventions. (orig.)

Creatinine clearance during cimetidine administration for measurement of glomerular filtration rate

NARCIS (Netherlands)

van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; de Waart, D. R.; Arisz, L.

1992-01-01

Creatinine clearance inaccurately estimates true glomerular filtration rate (GFR) because of tubular secretion of creatinine. We studied the ability of oral cimetidine, a blocker of tubular creatinine secretion, to improve the accuracy of measuring creatinine clearance. Clearances of inulin and

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...

Effect of kefir and low-dose aspirin on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet.

Science.gov (United States)

Kanbak, Güngör; Uzuner, Kubilay; Kuşat Ol, Kevser; Oğlakçı, Ayşegül; Kartkaya, Kazım; Şentürk, Hakan

2014-01-01

Abstract We aim to study the effect of low-dose aspirin and kefir on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet. Forty adult male Sprague-Dawley rats were divided into five groups: control, high-salt (HS) (8.0% NaCl), HS+aspirin (10 mg/kg), HS+kefir (10.0%w/v), HS+aspirin +kefir. We measured sistolic blood pressure (SBP), mean arterial pressure (MAP), diastolic pressure, pulse pressure in the rats. Cathepsin B, L, DNA fragmentation and caspase-3 activities were determined from rat kidney tissues and rats clearance of creatinine calculated. Although HS diet increased significantly SBP, MAP, diastolic pressure, pulse pressure parameters compared the control values. They were not as high as accepted hypertension levels. When compared to HS groups, kefir groups significantly decrease Cathepsin B and DNA fragmentation levels. Caspase levels were elevated slightly in other groups according to control group. While, we also found that creatinine clearance was higher in HS+kefir and HS+low-dose aspirin than HS group. Thus, using low-dose aspirin had been approximately decreased of renal function damage. Kefir decreased renal function damage playing as Angiotensin-converting enzyme inhibitor. But, low-dose aspirin together with kefir worsened rat renal function damage. Cathepsin B might play role both apoptosis and prorenin-processing enzyme. But not caspase pathway may be involved in the present HS diet induced apoptosis. In conclusion, kefir and low-dose aspirin used independently protect renal function and renal damage induced by HS diet in rats.

The influence of partial renal function impairment on thyroid hormones level in acute renal failure-ARF patients

International Nuclear Information System (INIS)

Ilic, S.; Vlajkovic, M.; Rajic, M.; Bogicevic, M.

2002-01-01

The aim of this study was to assess the relationship of thyroid hormone levels with glomerular and tubular renal function in ARF. In thirty one patients with different underlying diseases, glomerular filtration (GFR) was estimated by measuring 99mTc-DTPA clearance and tubular function by 131I-OIH clearance. The thyroid status was evaluated by radioimmunoassays of T4, FT4, T3, FT3, rT3 and TSH, while the cortisol level was used to indicate the stress role. All the measurements were performed within 7 days as well after 1,3,6 and 12 months from the ARF onset. The results obtained were compared with those of 30 healthy subjects. At the ARF beginning, the impairment of renal function was manifested by the fall of 99mTc-DTPA clearance to 21∫7ml/min and 131I-OIH clearance to 172±34ml/min, while end values were 77±19ml/min and 395±70ml/min, respectively. The hormone analysis within 7 days, showed T3 decrease to 1.21±0.16nmol/l and the increase rT3 to 38±7ng/1ooml, as well as cortisol to 350±71ng/ml, but at the end of the study these hormone levels were normalized. Other hormone levels didn't differ significantly from control values. Regression analysis established significant correlation of 99mTc-DTPA clearance with T3 (r=0.693, p 100, OIH>500), partial recovery (DTPA 51-100, OIH 250-500) and without any recovery (DTPA<50,OIH<250), showed hormone disturbances proportional to the degree of renal function damage. The most severe disorders were found in the third group, where both total and free T4 and T3 were lowered, while rT3 and cortisol elevated at 7th day from ARF onset. After 12 months all these values associated with that of TSH were observed as declined.This study suggests thyroid hormone levels to be dependent on the renal function in ARF. Greater impairment of glomerular related to tubular function appears to be more responsible for thyroid dysfunction, due to uremic toxins retention as well as stress induced by the extreme function failure

The effects of cimetidine on creatinine excretion, glomerular filtration rate and tubular function in renal transplant recipients

DEFF Research Database (Denmark)

Olsen, N V; Ladefoged, S D; Feldt-Rasmussen, B

1989-01-01

The renal clearance of endogenous creatinine (CCr), sodium (CNa) and lithium (CLi) was determined before and after a single intravenous bolus of cimetidine in nine renal transplant recipients. The glomerular filtration rate (GFR) was measured with 125I-iothalamate clearance (CTh). The initial CCr...... tubular flow. This suggests that on-going cimetidine treatment must be taken into account when graft function is evaluated by the CCr alone....

Renal functional recovery of the hydronephrotic kidney predicted before relief of the obstruction

International Nuclear Information System (INIS)

McDougal, W.S.; Flanigan, R.C.

1981-01-01

Employing technetium labeled dimercaptosuccinic acid, we predicted the inulin and p-aminohippuric acid (PAH) clearances after recovery of an obstructed kidney before relief of the obstruction. Sixteen rabbits had one renal unit obstructed for varying period of time. The animals were scanned immediately before relief of the obstruction. After 4 to 6 months recovery, inulin and PAH clearances were measured in all animals. The scans were mathematically analyzed, and accurately predicted the inulin and PAH clearances obtained after complete recovery (P less than 0.001 and P less than 0.001, respectively). Six rabbits were scanned at the time of the clearance measurements. By a different mathematical analysis, inulin and PAH clearance measured concurrently correlated with the scan

Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats

DEFF Research Database (Denmark)

Thomsen, Klaus; Shirley, David G

2007-01-01

Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular...... fluid output (assessed by lithium clearance) and excretion rates. The present study examined the reason for these increases. The first series of experiments showed that one cause is volume overloading. This can occur if the servo system is activated from the start, i.e., during the establishment...... not seen when blood samples are replaced with the animal's own red blood cells resuspended in isotonic saline. When these pitfalls are avoided, servo-controlled sodium and fluid replacement is a reliable technique that makes it possible to study the effects of natriuretic and/or diuretic stimuli without...

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

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.

Anatomical and physiological basis for the allometric scaling of cisplatin clearance in dogs.

Science.gov (United States)

Achanta, S; Sewell, A; Ritchey, J W; Broaddus, K; Bourne, D W A; Clarke, C R; Maxwell, L K

2016-06-01

Cisplatin is a platinum-containing cytotoxic drug indicated for the treatment of solid tumors in veterinary and human patients. Several of the algorithms used to standardize the doses of cytotoxic drugs utilize allometry, or the nonproportional relationships between anatomical and physiological variables, but the underlying basis for these relationships is poorly understood. The objective of this proof of concept study was to determine whether allometric equations explain the relationships between body weight, kidney weight, renal physiology, and clearance of a model, renally cleared anticancer agent in dogs. Postmortem body, kidney, and heart weights were collected from 364 dogs (127 juveniles and 237 adults, including 51 dogs ≥ 8 years of age). Renal physiological and cisplatin pharmacokinetic studies were conducted in ten intact male dogs including two juvenile and eight adult dogs (4-55 kg). Glomerular filtration rate (GFR), effective renal plasma flow, effective renal blood flow, renal cisplatin clearance, and total cisplatin clearance were allometrically related to body weight with powers of 0.75, 0.59, 0.61, 0.71, and 0.70, respectively. The similar values of these diverse mass exponents suggest a common underlying basis for the allometry of kidney size, renal physiology, and renal drug handling. © 2015 John Wiley & Sons Ltd.

Residual kidney function after donor nephrectomy. Assessment by 99mTc-MAG3-Clearance

International Nuclear Information System (INIS)

Hamscho, N.; Doebert, N.; Menzel, C.; Berner, U.; Zaplatnikov, K.; Gruenwald, F.; Wilhelm, A.; Gossmann, J.; Scheuermann, E.H.

2005-01-01

Aim: We evaluated the long-term residual renal function after donor nephrectomy using 99m Tc-mercaptoacetyltriglycin (MAG3)-clearance. Donors, methods: Altogether 49 kidney donors were examined using 99m Tc-MAG3-clearance after nephrectomy for donation to a relative (m:f=11.38; age 55±27 years). The donors were examined 16±8 years postoperatively (1.5-26 years). 42 donors (86%) showed normal creatinine values, whereas the other seven (14%) exhibited slightly elevated levels. 20 donors were examined pre- and postoperatively and compared intraindividually. The kidney function was compared to the age adapted normal values of healthy persons with two kidneys (67-133% of age related mean). Results: After nephrectomy all donors showed a normal perfusion, good secretion, merely physiological intrarenal transit and a normal elimination from the kidneys. The 99m Tc-MAG3-clearance was 69±15% of the normal mean value of healthy carriers of two kidneys regardless of the gender. 20 donors with a preoperative examination showed a significantly reduced total renal function from 84±15% of the mean normal value preoperatively to 60±15% postoperatively (p 99m Tc-MAG3-clearance measured prior to nephrectomy and the clearance levels after nephrectomy. Also, no correlation between the preoperative 99m Tc-MAG3-clearance and the postoperative serum creatinine values could be observed. Althogether, 22% of the donors (11/49) developed arterial hypertension 10±8 years after donation (1-23 years). This corresponds to the normal age prevalence of hypertension in the carriers of two kidneys. Three donors suffered from arterial hypertension prior to the operation. Conclusion: Kidney donors with normal or slightly elevated creatinine values postoperatively show a 99m Tc-MAG3 clearance value of 69% of the mean value of healthy carriers of two kidneys. This may serve as a reference value for healthy carriers of one kidney. In our study we demonstrated a good compensation of the contralateral

A comparison of two nuclear-medical techniques for effective renal plasma flow determination in rabbits: Radiation controlled infusion-pump and whole-body measurement according to Oberhausen

International Nuclear Information System (INIS)

Mayer-Wehrstein, R.

1981-01-01

Two nuclear techniques were investigated for determination of the effective renal plasma flow with J-131-Hippuran in rabbits: whole-body measurement according to Oberhausen and clearance determination with a radiation controlled feed back infusion pump. In the first method the clearance determination follows after a single injection of the testing substance in the decreasing phase of the blood level, in the second method a constant blood level of the testing substance is maintained. A technique was developed for the determination of the blood-tissue ratio by considering the values determined by the constant blood level. This way the exact clearance values were computet for the decreasing plasma level. Nineteen clearance determinations were performed in rabbits altogether. (orig.) [de

Dosing of cytotoxic chemotherapy: impact of renal function estimates on dose.

Science.gov (United States)

Dooley, M J; Poole, S G; Rischin, D

2013-11-01

Oncology clinicians are now routinely provided with an estimated glomerular filtration rate on pathology reports whenever serum creatinine is requested. The utility of using this for the dose determination of renally excreted drugs compared with other existing methods is needed to inform practice. Renal function was determined by [Tc(99m)]DTPA clearance in adult patients presenting for chemotherapy. Renal function was calculated using the 4-variable Modification of Diet in Renal Disease (4v-MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Cockcroft and Gault (CG), Wright and Martin formulae. Doses for renal excreted cytotoxic drugs, including carboplatin, were calculated. The concordance of the renal function estimates according to the CKD classification with measured Tc(99m)DPTA clearance in 455 adults (median age 64.0 years: range 17-87 years) for the 4v-MDRD, CKD-EPI, CG, Martin and Wright formulae was 47.7%, 56.3%, 46.2%, 56.5% and 60.2%, respectively. Concordance for chemotherapy dose for these formulae was 89.0%, 89.5%, 85.1%, 89.9% and 89.9%, respectively. Concordance for carboplatin dose specifically was 66.4%, 71.4%, 64.0%, 73.8% and 73.2%. All bedside formulae provide similar levels of concordance in dosage selection for the renal excreted chemotherapy drugs when compared with the use of a direct measure of renal function.

Plasma Creatinine Clearance in the Dog

Science.gov (United States)

Frazier, Loy W.

1977-01-01

Lists materials and methods for an experiment that demonstrates the concept of glomerular filtration rate (GFR) using anesthesized dogs. In the dog, GFR is equivalent to the renal plasma clearance of exogenous creatinine. (CS)

A dosing algorithm for metformin based on the relationships between exposure and renal clearance of metformin in patients with varying degrees of kidney function.

Science.gov (United States)

Duong, Janna K; Kroonen, M Y A M; Kumar, S S; Heerspink, H L; Kirkpatrick, C M; Graham, G G; Williams, K M; Day, R O

2017-08-01

The aims of this study were to investigate the relationship between metformin exposure, renal clearance (CL R ), and apparent non-renal clearance of metformin (CL NR /F) in patients with varying degrees of kidney function and to develop dosing recommendations. Plasma and urine samples were collected from three studies consisting of patients with varying degrees of kidney function (creatinine clearance, CL CR ; range, 14-112 mL/min). A population pharmacokinetic model was built (NONMEM) in which the oral availability (F) was fixed to 0.55 with an estimated inter-individual variability (IIV). Simulations were performed to estimate AUC 0-τ , CL R , and CL NR /F. The data (66 patients, 327 observations) were best described by a two-compartment model, and CL CR was a covariate for CL R . Mean CL R was 17 L/h (CV 22%) and mean CL NR /F was 1.6 L/h (69%).The median recovery of metformin in urine was 49% (range 19-75%) over a dosage interval. When CL R increased due to improved renal function, AUC 0-τ decreased proportionally, while CL NR /F did not change with kidney function. Target doses (mg/day) of metformin can be reached using CL CR /3 × 100 to obtain median AUC 0-12 of 18-26 mg/L/h for metformin IR and AUC 0-24 of 38-51 mg/L/h for metformin XR, with C max  kidney function to maintain consistent drug exposure. However, there is still marked IIV and therapeutic drug monitoring of metformin plasma concentrations is recommended.

Comparison of gas clearance and radioactive microspheres for pancreatic blood flow measurement

International Nuclear Information System (INIS)

DeMar, A.R.; Graham, L.S.; Lake, R.; Fink, A.S.

1989-01-01

Measurement of pancreatic blood flow (PBF) is technically demanding. Although radiolabeled microspheres are considered the gold standard for PBF assessment, they have practical limitations. In the current study, H 2 and xenon-133 gas clearance techniques were adapted to PBF measurement and compared to radiolabeled microsphere techniques. Simultaneous measurements of PBF were made using either hydrogen or xenon gas washout and radiolabeled microspheres. Measurements were made under basal, vasoconstricted (vasopressin 2U i.v. or nicotine 4 micrograms/kg/h) and stimulated (secretin 125 ng/kg/h or 2 U/kg i.v.) conditions (random order). Mean PBF was 26.9 +/- 5.3, 50.5 +/- 2.3 and 27.6 +/- 5.2 ml/min/100 g basally, 36.9 +/- 8.0, 90.1 +/- 18.9, and 81.7 +/- 14.5 ml/min/100 g in the stimulated state, and 24.2 +/- 7.8, 25.0 +/- 3.5, and 14.9 +/- 7.5 ml/min/100 g in the vasoconstricted state for hydrogen gas clearance, xenon gas clearance, and radiolabeled microspheres, respectively. The H 2 clearance technique resulted in tissue trauma, was complicated by frequent electrode displacement, and correlated poorly (r2 = 0.36, p greater than 0.05) with microsphere values. In contrast, xenon clearance measurement had no apparent effect on the pancreas and correlated well (r2 = 0.83, p less than 0.01) with microsphere data. We conclude that xenon clearance offers an attractive, validated alternative to radiolabeled microspheres for measuring pancreatic blood flow

Role of serum creatinine for screening renal diseases

International Nuclear Information System (INIS)

Younas, M.; Khan, F.A.; Sattar, A.; Kazmi, A.

2011-01-01

Chronic kidney disease (CKD) is a public Heath problem with increasing prevalence in Pakistan. Early identification of mild renal disease can delay its progression. Glomerular filtration rate (GFR) is the best overall index of renal function, but it is difficult to measure, so mostly clinicians rely on. serum creatinine (SCr) concentration which its own limitations. On the other hand 24 hours (h) urinary creatinine clearance (CICl) is a more sensitive marker of renal dysfunction. Presently SCr is being used in our clinical practice to screen the renal diseases which can miss mild renal dysfunctions, so this study was designed to calculate frequency of individuals having reduced GFR as determined by CrCI having normal SCr levels. (author)

Non-destructive clearance measuring in closed joints

International Nuclear Information System (INIS)

Doucelance, C.; Manaranche, J.C.

1976-01-01

Two methods for clearance measuring in closed joints are described. The first one is based on the mechanical impedance concept, while the other one requires a shock test on shaker. Both are illustrated with an example of application [fr

Effect of renal venous pressure elevation on tubular sodium and water reabsorption in the dog kidney

DEFF Research Database (Denmark)

Abildgaard, U; Amtorp, O; Holstein-Rathlou, N H

1988-01-01

of [51Cr]EDTA was used as a measure of the rate of glomerular filtration (GFR). GFR, urinary excretion rates of sodium and water, and lithium clearance were used for assessing the absolute and fractional reabsorption rates of sodium and water in the proximal as well as in more distal segments......This study was performed in order to quantify the effects of renal venous pressure (RVP) elevation on absolute and fractional reabsorption rates of sodium and water in proximal and distal segments of the nephron in dog kidneys. Renal blood flow (RBF) was measured electromagnetically. Clearance...

Genetic variation underlying renal uric acid excretion in Hispanic children: the Viva La Familia Study.

Science.gov (United States)

Chittoor, Geetha; Haack, Karin; Mehta, Nitesh R; Laston, Sandra; Cole, Shelley A; Comuzzie, Anthony G; Butte, Nancy F; Voruganti, V Saroja

2017-01-17

Reduced renal excretion of uric acid plays a significant role in the development of hyperuricemia and gout in adults. Hyperuricemia has been associated with chronic kidney disease and cardiovascular disease in children and adults. There are limited genome-wide association studies associating genetic polymorphisms with renal urate excretion measures. Therefore, we investigated the genetic factors that influence the excretion of uric acid and related indices in 768 Hispanic children of the Viva La Familia Study. We performed a genome-wide association analysis for 24-h urinary excretion measures such as urinary uric acid/urinary creatinine ratio, uric acid clearance, fractional excretion of uric acid, and glomerular load of uric acid in SOLAR, while accounting for non-independence among family members. All renal urate excretion measures were significantly heritable (p uric acid clearance with a single nucleotide polymorphism (SNP) in zinc finger protein 446 (ZNF446) (rs2033711 (A/G), MAF: 0.30). The minor allele (G) was associated with increased uric acid clearance. Also, we found suggestive associations of uric acid clearance with SNPs in ZNF324, ZNF584, and ZNF132 (in a 72 kb region of 19q13; p <1 × 10 -6 , MAFs: 0.28-0.31). For the first time, we showed the importance of 19q13 region in the regulation of renal urate excretion in Hispanic children. Our findings indicate differences in inherent genetic architecture and shared environmental risk factors between our cohort and other pediatric and adult populations.

Glomerular filtration rate measured by 51Cr-EDTA clearance: evaluation of captopril-induced changes in hypertensive patients with and without renal artery stenosis

International Nuclear Information System (INIS)

Chaves, Anna Alice Rolim; Buchpiguel, Carlos Alberto; Praxedes, Jose Nery; Bortolotto, Luiz Aparecido; Sapienza, Marcelo Tatit

2010-01-01

Introduction: renal artery stenosis can lead to renovascular hypertension; however, the detection of stenosis alone does not guarantee the presence of renovascular hypertension. Renovascular hypertension depends on activation of the renin-angiotensin system, which can be detected by functional tests such as captopril renal scintigraphy. A method that allows direct measurement of the baseline and post-captopril glomerular filtration rate using chromium-51 labeled ethylenediamine tetraacetic acid ( 51 Cr-EDTA) could add valuable information to the investigation of hypertensive patients with renal artery stenosis. The purposes of this study were to create a protocol to measure the baseline and post-captopril glomerular filtration rate using 51 Cr-EDTA, and to verify whether changes in the glomerular filtration rate permit differentiation between hypertensive patients with and without renal artery stenosis. Methods: this prospective study included 41 consecutive patients with poorly controlled severe hypertension. All patients had undergone a radiological investigation of renal artery stenosis within the month prior to their inclusion. The patients were divided into two groups: patients with (n=21) and without renal artery stenosis, (n=20). In vitro glomerular filtration rate analysis ( 51 Cr-EDTA) and 99m Tc-DMSA scintigraphy were performed before and after captopril administration in all patients. Results: the mean baseline glomerular filtration rate was 48.6±21.8 ml/kg/1.73 m 2 in the group with renal artery stenosis, which was significantly lower than the GFR of 65.1±28.7 ml/kg/1.73m 2 in the group without renal artery stenosis (p=0.04). Captopril induced a significant reduction of the glomerular filtration rate in the group with renal artery stenosis (to 32.6±14.8 ml/kg/1.73m 2 , p=0.001) and an insignificant change in the group without RAS (to 62.2±23.6 ml/kg/1.73m 2 , p=0.68). Scintigraphy with technetium-99m dimercapto-succinic acid (DMSA) did not show

The effects of cimetidine on creatinine excretion, glomerular filtration rate and tubular function in renal transplant recipients

DEFF Research Database (Denmark)

Olsen, N V; Ladefoged, S D; Feldt-Rasmussen, B

1989-01-01

The renal clearance of endogenous creatinine (CCr), sodium (CNa) and lithium (CLi) was determined before and after a single intravenous bolus of cimetidine in nine renal transplant recipients. The glomerular filtration rate (GFR) was measured with 125I-iothalamate clearance (CTh). The initial CCr...... of 65 ml/min (median) was reduced to a nadir of 46 ml/min (p less than 0.01) during the first 2 h after infusion of cimetidine. GFR remained unchanged, and thus the fractional clearance of creatinine (CCr/CTh) was reduced from 1.43 (median) to 1.03 (p less than 0.01). CNa and the fractional excretion...... of sodium decreased throughout the study (p less than 0.05); CLi was unchanged. In conclusion cimetidine, when measured during 1-h clearance periods, interferes with tubular creatinine secretion in the denervated kidney of transplant recipients without affecting the glomerular filtration rate or proximal...

A study for promoting measures of social acceptance on clearance system

International Nuclear Information System (INIS)

Okoshi, Minoru; Torii, Hiroyuki; Fujii, Yasuhiko

2007-01-01

Clearance is one of the useful concepts to manage large amounts of slightly contaminated solid radioactive materials generated from the decommissioning of nuclear facilities. Cleared materials are expected to be disposed of as conventional wastes or recycled to produce consumer goods. In Japan, the legal frame-work for clearance was established in 2005 by amending the Law to regulate nuclear materials, reactors and so on. However, it is not so clear whether the general public understands clearance well. In this paper, major concerns about clearance from the general public are analyzed based on the public comments for reports on clearance prepared by the Nuclear Safety Commission and the Nuclear Institute Safety Agency. The major anxieties for clearance expressed by the general public are the safety of clearance, unknown factors of radiation effects, possibilities of excess radiation exposure due to inadequate measurements of radioactivities and fairness in decision making. In order to deal with those anxieties, some countermeasures including the confidence in nuclear operators and regulatory authorities and controllability of clearance by the general public are discussed to promote the social acceptance of clearance by the general public. (author)

Effect of nitrendipine on renal function and on hormonal parameters after intravascular iopromide

DEFF Research Database (Denmark)

Madsen, J K; Jensen, J W; Sandermann, J

1998-01-01

PURPOSE: To evaluate the effect of the low-molecular nonionic radiographic contrast agent iopromide (Ultravist) on renal function, vasoactive peptides (angiotensin II, aldosterone, arginine vasopressin, and atrial natriuretic factor (ANF)), and blood pressure, and to evaluate the influence....... Renal tubular function was estimated from the clearance of lithium. Hormones were measured by radioimmunoassays. RESULTS: Arteriography with iopromide did not change renal function. No differences between the nitrendipine and placebo groups were found in renal hemodynamics, tubular sodium handling...

Predictive factors of lower calyceal stone clearance after extracorporeal shockwave lithotripsy (ESWL): the impact of radiological anatomy.

Science.gov (United States)

Lin, Chih-Chieh; Hsu, Yen-Shen; Chen, Kuang-Kuo

2008-10-01

This study was carried out to determine whether or not there is a significant relationship between the radiologic anatomy of the lower calyx, as seen on preoperative intravenous urography (IVU), and the outcome of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for lower renal calyceal stones. Between June 1998 and April 2007, 112 patients with a solitary lower renal calyceal stone measuring 20 mm or less in size were enrolled in this retrospective study. Pretreatment IVU was reviewed for measuring the anatomical predictors, such as lower pole infundibular length, infundibular width (IW) and infundibulopelvic angle, while the stone location and size were determined on plain abdominal X-ray. All patients were treated with ESWL using a Siemens Lithostar Plus lithotriptor and were followed-up for the outcome of stone clearance 3 months after ESWL with plain abdominal X-ray films and ultrasonography. Three months after ESWL, only 49 (43.7%) patients were stone-free. Under multivariate analysis with logistic regression, smaller stone size (10 mm or less, p = 0.005) and greater IW (4 mm or more, p = 0.029) were significant favourable predictors for better stone clearance. In addition to the influence of stone size, lower pole anatomy, especially IW, has a significant impact on stone clearance for lower calyceal stone after ESWL.

Increased renal production of C-type natriuretic peptide (CNP) in patients with cirrhosis and functional renal failure

DEFF Research Database (Denmark)

Gülberg, V; Møller, S; Henriksen, Jens Henrik Sahl

2000-01-01

homeostasis. Therefore, the aim of the present study was to investigate the possible role of CNP in renal function disturbances in patients with cirrhosis of the liver. METHODS: Peripheral venous and urinary concentrations of CNP were determined in samples from 11 healthy controls, 20 cirrhotic patients...... with normal renal function (creatinine clearance 117 (8) ml/min), and 20 cirrhotic patients with impaired renal function (creatinine clearance 35 (4) ml/min). In a second protocol, arterial and renal venous plasma concentrations of CNP were determined in 37 patients with cirrhosis of the liver to estimate...... renal extraction ratios of CNP. A sensitive and specific radioimmunoassay was applied after solid phase extraction of samples. RESULTS: Plasma CNP was lower in cirrhotic patients with normal and impaired renal function than in controls (3.0 (0.4) and 2.7 (0.2) v. 4.2 (0.4) pg/ml, respectively; p

Alpha radioactivity measurement technology with ionized air type measurement. Applicability evaluation to verification of the clearance level

International Nuclear Information System (INIS)

Mita, Yutaka; Matsumura, Toshihiro; Yokoyama, Kaoru; Sugitsue, Noritake

2008-10-01

The purpose of this test is to evaluate the applicability of the clearance level measuring system by Ionized Air Type Measurement after decontaminated by sulfuric acid sample. In Ningyo-toge Environmental Engineering Center. The equipment and radioactive waste which were contaminated with uranium are generated so much in future dismantling stage. In our plan, some of equipments and radioactive waste are contaminated to a clearance level, and cut down on decommission and disposal expense. This plan needs the alpha-rays measurement technology of the very low level. We think that ionized Air transfer measurement technology is promising as of clearance verification technology. The ionized Air transfer measurement technology applied to the Ionized Air Type Measurement can measure plan radioactivity of a very low level. Moreover, as compared with a direct survey, there is the merit which can be measured in a short time. However ionized Air transfer measurement technology is new technology. Therefore, there is almost no measurement track record. Furthermore, the date about the influence of a background, a detection limit, measurement performance, and reliability is insufficient. So, this measurement test estimated applicability as clearance level verification of an Ionized Air Type Measurement. (author)

Cerebrospinal Fluid Clearance in Alzheimer Disease Measured with Dynamic PET.

Science.gov (United States)

de Leon, Mony J; Li, Yi; Okamura, Nobuyuki; Tsui, Wai H; Saint-Louis, Les A; Glodzik, Lidia; Osorio, Ricardo S; Fortea, Juan; Butler, Tracy; Pirraglia, Elizabeth; Fossati, Silvia; Kim, Hee-Jin; Carare, Roxana O; Nedergaard, Maiken; Benveniste, Helene; Rusinek, Henry

2017-09-01

Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing the cribriform plate, human CSF clearance pathways are not well characterized. Dynamic PET with 18 F-THK5117, a tracer for tau pathology, was used to estimate the ventricular CSF time-activity as a biomarker for CSF clearance. We tested 3 hypotheses: extracranial CSF is detected at the superior turbinates; CSF clearance is reduced in AD; and CSF clearance is inversely associated with amyloid deposition. Methods: Fifteen subjects, 8 with AD and 7 normal control volunteers, were examined with 18 F-THK5117. Ten subjects additionally underwent 11 C-Pittsburgh compound B ( 11 C-PiB) PET scanning, and 8 were 11 C-PiB-positive. Ventricular time-activity curves of 18 F-THK5117 were used to identify highly correlated time-activity curves from extracranial voxels. Results: For all subjects, the greatest density of CSF-positive extracranial voxels was in the nasal turbinates. Tracer concentration analyses validated the superior nasal turbinate CSF signal intensity. AD patients showed ventricular tracer clearance reduced by 23% and 66% fewer superior turbinate CSF egress sites. Ventricular CSF clearance was inversely associated with amyloid deposition. Conclusion: The human nasal turbinate is part of the CSF clearance system. Lateral ventricle and superior nasal turbinate CSF clearance abnormalities are found in AD. Ventricular CSF clearance reductions are associated with increased brain amyloid depositions. These data suggest that PET-measured CSF clearance is a biomarker of potential interest in AD and other neurodegenerative diseases. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

A comparison of analytic procedures for measurement of fractional dextran clearances

NARCIS (Netherlands)

Hemmelder, MH; de Jong, PE; de Zeeuw, D

Fractional dextran clearances have been extensively used to study glomerular size selectivity. We report on an analysis of different laboratory procedures involved in measuring fractional dextran clearances. The deproteinization of plasma samples by 20% trichloroacetic acid (TCA) revealed a protein

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.

Single injection 51Cr EDTA plasma clearance determination in children using capillary blood samples

International Nuclear Information System (INIS)

Broechner-Mortensen, J.; Christoffersen, J.

1977-01-01

The reliability of a determination of the total 51 Cr EDTA plasma clearance (e) (and with it the glomerular filtration rate), by a simplified single injection method (injected dose: 4.5 μCi per kg b.w.) using capillary blood samples (0.2 ml), was investigated in twenty children. Clearance values determined from capillary blood samples did not differ significantly from those measured simultaneously from venous blood samples, the mean ratio+-SD being 1.02+-0.06(n = 10). The reproducibility (total day-to-day variation) of E determined from capillary blood samples was 6.7% in children with decreased renal function (n = 3) and 6.9% in children with normal renal function (n = 7). The present data indicate that the use of capillary blood samples is an accurate and very precise approach for determination of E in children. (Auth.)

Servo-control of water and sodium homeostasis during renal clearance measurements in conscious rats.

Science.gov (United States)

Thomsen, Klaus; Shirley, David G

2007-01-01

Servo-controlled fluid and sodium replacement during clearance studies is used in order to prevent loss of body fluid and sodium following diuretic/natriuretic procedures. However, even under control conditions, the use of this technique is sometimes associated with increases in proximal tubular fluid output (assessed by lithium clearance) and excretion rates. The present study examined the reason for these increases. The first series of experiments showed that one cause is volume overloading. This can occur if the servo system is activated from the start, i.e., during the establishment of a suitably high urine flow rate by constant infusion of hypotonic glucose solution. The second series of experiments showed that replacement of blood samples with donor blood can also lead to increases in fractional lithium excretion and accompanying increases in water and sodium excretion, a problem not seen when blood samples are replaced with the animal's own red blood cells resuspended in isotonic saline. When these pitfalls are avoided, servo-controlled sodium and fluid replacement is a reliable technique that makes it possible to study the effects of natriuretic and/or diuretic stimuli without interference from unwanted changes in extracellular volume. 2007 S. Karger AG, Basel

Effect of metabolic regulation on renal leakiness to dextran molecules in short-term insulin-dependent diabetics

DEFF Research Database (Denmark)

Parving, H H; Rutili, F; Granath, K

1979-01-01

Renal clearance of dextran of two ranges of molecular size and glomerular filtration rate (GFR, 51Cr-EDTA) were measured in seven short-term insulin-dependent diabetics (mean age 25 years). Measurements were carried out in the same patient during good and poor metabolic regulation (plasma glucose......, mean +/- SEM, 6.5 +/- 0.9 and 14.8 +/- 1.5 mmol/l, respectively). GFR was elevated in all patients during poor metabolic regulation (119 +/- 6 ml/min/1.73 m2, versus 99 +/- 2 ml/min/1.73 m2 during good control, p less than 0.01). The average renal clearance of dextran with molecular weights ranging...... from 25,000 to 35,000 and 35,000 to 45,000 increased during poor metabolic regulation from 14.8 +/- 0.8 to 19.8 +/- 1.8 ml/min/1.73 m2, and 5.2 +/- 0.3 to 6.8 +/- 0.6 ml/min/1.73 m2, respectively (p less than 0.05). The elevated GFR and renal dextran clearance found during poor metabolic regulation...

[Renal excretion of methylene-diphosphate-technium-99m. Preliminary observations].

Science.gov (United States)

Vattimo, A; Martini, G

1983-11-30

The purpose of this study is to elucidate the mechanism of the renal excretion of 99mTc-MDP in man. We compared the renal clearance of 99mTc-MDP and 51Cr-EDTA (glomerular filtration rate agent). Since the 99mTc-MDP is bound to the plasma protein, the free fraction was calculated by dialysis. The clearances were obtained by single-injection technique. The plasma disappearance of the tracers was resolved into three exponential functions and area was calculated. The clearance was calculated by dividing the amount of the tracers excreted during the first four hours and the plasma area. In this study no difference was found in the clearance of the two agents. These findings suggest that the renal excretion of diphosphonate is related to the glomerular filtration rate.

Clearance of glucoregulatory peptide hormones during haemodialysis and haemodiafiltration in non-diabetic end-stage renal disease patients

DEFF Research Database (Denmark)

Jørgensen, Morten B; Idorn, Thomas; Knop, Filip K

2015-01-01

BACKGROUND: Patients with end-stage renal disease (ESRD) have increased fasting concentrations and disturbed postprandial responses of several glucoregulatory hormones. We aimed to evaluate the impact of high-flux haemodialysis (HD) and high-volume haemodiafiltration (HDF) on fasting and postpran......BACKGROUND: Patients with end-stage renal disease (ESRD) have increased fasting concentrations and disturbed postprandial responses of several glucoregulatory hormones. We aimed to evaluate the impact of high-flux haemodialysis (HD) and high-volume haemodiafiltration (HDF) on fasting...... and postprandial plasma levels of glucoregulatory pancreatic and gut peptide hormones in ESRD patients. METHODS: Ten non-diabetic HD-treated ESRD patients were included to undergo a 3-h standardized liquid mixed meal test 1 h into an HD and an HDF, respectively. On a third, optional, examination day, the meal test...... during HDF and four completed the optional meal test without dialysis. All plasma hormone concentrations declined significantly during the first fasting hour of dialysis with no differences between HD and HDF. Significant clearance of the investigated hormones was observed for both dialysis modalities...

Development of a Novel System to Measure a Clearance of a Passenger Platform

Science.gov (United States)

Shimizu, M.; Oizumi, J.; Matsuoka, R.; Takeda, H.; Okukura, H.; Ooya, A.; Koike, A.

2016-06-01

Clearances of a passenger platform at a railway station should be appropriately maintained for safety of both trains and passengers. In most Japanese railways clearances between a platform and a train car is measured precisely once or twice a year. Because current measurement systems operate on a track, the closure of the track is unavoidable. Since the procedure of the closure of a track is time-consuming and bothersome, we decided to develop a new system to measure clearances without the closure of a track. A new system is required to work on a platform and the required measurement accuracy is less than several millimetres. We have adopted a 3D laser scanner and stop-and-go operation for a new system. The current systems on a track measure clearances continuously at walking speed, while our system on a platform measures clearances at approximately ten metres intervals. The scanner controlled by a PC acquires a set of point data at each measuring station. Edge points of the platform, top and side points of two rails are detected from the acquired point data. Finally clearances of the platform are calculated by using the detected feature points of the platform and the rails. The results of an experiment using a prototype of our system show that the measurement accuracy by our system would be satisfactory, but our system would take more time than the current systems. Since our system requires no closure of a track, we conclude that our system would be convenient and effective.

Pulsatility index of renal artery in patients with liver cirrhosis

International Nuclear Information System (INIS)

Baik, Soon Koo; Kim, Kwan Hyun; Jeong, Yon Soo; Kim, Hyun Soo; Lee, Dong Ki; Kwon, Sang Ok

2000-01-01

As one of non-invasive methods evaluating disorders of renal perfusion using Doppler ultrasonography, PI represents the characteristics of the Doppler waveform more accurately than RI, and even when renal perfusion is severely impaired, objective estimation is possible because of using the mean velocity in its calculation. The purpose of this study is to find out the clinical usefulness of PI for evaluating disorder of renal function in patients with liver cirrhosis. The subjects were 167 patients including 89 of Child A and B groups, 39 of Child C group, and 39 of control group. We compared PI, RI, creatinine, serum renin activity and aldosterone level between each groups, and investigated the relationships of PI with creatinine clearance, serum renin activity, and aldosterone level. Meal PI was 1.00 ± 0.15 in control group, 1.17 ± 0.22 in Child A and B groups, and 1.30 ± 0.28 in Child C group, which showed significant difference between each groups (p<0.05). Also RI, creatinine clearance, serum renin activity and aldosterone level revealed significant difference between each groups (p<0.05). PI showed significant negative relationships with creatinine clearance (p=0.009), serum renin activity (p=0.06), and aldosterone level (p=0.001). Measurement of PI by Doppler ultrasonography is a useful non-invasive method for evaluation renal dysfunction in patients with liver cirrhosis.

High Phenobarbital Clearance During Continuous Renal Replacement Therapy

Science.gov (United States)

Rosenborg, Staffan; Saraste, Lars; Wide, Katarina

2014-01-01

Abstract Phenobarbital is an old antiepileptic drug used in severe epilepsy. Despite this, little is written about the need for dose adjustments in renal replacement therapy. Most sources recommend a moderately increased dose guided by therapeutic drug monitoring. A 14 year old boy with nonketotic hyperglycinemia, a rare inborn error of metabolism, characterized by high levels of glycine, epilepsy, spasticity, and cognitive impairment, was admitted to the emergency department with respiratory failure after a few days of fever and cough. The boy was unconscious at admittance and had acute renal and hepatic failure. Due to the acute respiratory infection, hypoxic hepatic and renal failure occurred and the patient had a status epilepticus. The patient was intubated and mechanically ventilated. Continuous renal replacement therapy was initiated. Despite increased phenobarbital doses, therapeutic levels were not reached until the dose was increased to 500 mg twice daily. Therapeutic drug monitoring was performed in plasma and dialysate. Calculations revealed that phenobarbital was almost freely dialyzed. Correct dosing of drugs in patients on renal replacement therapy may need a multidisciplinary approach and guidance by therapeutic drug monitoring. PMID:25101986

Clinical significance of measurement of changes of plasma leptin and serum NPY levels after hemodialysis in patients with chronic renal failure

International Nuclear Information System (INIS)

Xia Zhengping

2010-01-01

Objective: To explore the clinical significance of changes of plasma leptin and serum NPY levels after hemodialysis in patients with chronic renal failure. Methods: Plasma leptin and serum NPY levels were measured with RIA both before and after hemodialysis in 31 patients with chronic renal failure as well as in 35 controls. Results: Before hemodialysis,plasma leptin and serum NPY levels were significantly higher in the patients than those in controls (P<0.01). After hemodialysis for 1 week the levels, though dropped markedly, still remained significantly higher than those in controls (P<0.05). Conclusion: The levels of leptin and NPY were significantly increased in patients with chronic renal failare. Hemodialysis could increase, the clearance rate of leptin and NPY and partially correct the levels with important clinical value. (authors)

Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

Energy Technology Data Exchange (ETDEWEB)

Schofer, O. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Koenig, G. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bartels, U. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bockisch, A. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Piepenburg, R. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Beetz, R. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Meyer, G. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany); Hahn, K. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany)

1995-11-01

Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm{sup 2} body surface) in addition to normal oral fluid intake, weight-related dose of {sup 99m}Tc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ``normal`` with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

International Nuclear Information System (INIS)

Schofer, O.; Koenig, G.; Bartels, U.; Bockisch, A.; Piepenburg, R.; Beetz, R.; Meyer, G.; Hahn, K.

1995-01-01

Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm 2 body surface) in addition to normal oral fluid intake, weight-related dose of 99m Tc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ''normal'' with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

Glomerular filtration rate measured by {sup 51}Cr-EDTA clearance: evaluation of captopril-induced changes in hypertensive patients with and without renal artery stenosis

Energy Technology Data Exchange (ETDEWEB)

Chaves, Anna Alice Rolim; Buchpiguel, Carlos Alberto; Praxedes, Jose Nery; Bortolotto, Luiz Aparecido; Sapienza, Marcelo Tatit, E-mail: annaalice100@yahoo.com.b [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Dept. de Neurologia

2010-07-01

Introduction: renal artery stenosis can lead to renovascular hypertension; however, the detection of stenosis alone does not guarantee the presence of renovascular hypertension. Renovascular hypertension depends on activation of the renin-angiotensin system, which can be detected by functional tests such as captopril renal scintigraphy. A method that allows direct measurement of the baseline and post-captopril glomerular filtration rate using chromium-51 labeled ethylenediamine tetraacetic acid ({sup 51}Cr-EDTA) could add valuable information to the investigation of hypertensive patients with renal artery stenosis. The purposes of this study were to create a protocol to measure the baseline and post-captopril glomerular filtration rate using {sup 51}Cr-EDTA, and to verify whether changes in the glomerular filtration rate permit differentiation between hypertensive patients with and without renal artery stenosis. Methods: this prospective study included 41 consecutive patients with poorly controlled severe hypertension. All patients had undergone a radiological investigation of renal artery stenosis within the month prior to their inclusion. The patients were divided into two groups: patients with (n=21) and without renal artery stenosis, (n=20). In vitro glomerular filtration rate analysis ({sup 51}Cr-EDTA) and {sup 99m}Tc-DMSA scintigraphy were performed before and after captopril administration in all patients. Results: the mean baseline glomerular filtration rate was 48.6+-21.8 ml/kg/1.73 m{sup 2} in the group with renal artery stenosis, which was significantly lower than the GFR of 65.1+-28.7 ml/kg/1.73m{sup 2} in the group without renal artery stenosis (p=0.04). Captopril induced a significant reduction of the glomerular filtration rate in the group with renal artery stenosis (to 32.6+-14.8 ml/kg/1.73m{sup 2}, p=0.001) and an insignificant change in the group without RAS (to 62.2+-23.6 ml/kg/1.73m{sup 2}, p=0.68). Scintigraphy with technetium-99m dimercapto

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)

Clearance measurements on activated parts of accelerators by combined methods; Verfahrenskombinierte Freigabemessung aktivierter Beschleunigerteile

Energy Technology Data Exchange (ETDEWEB)

Jansen, S.; Friedemann, S. [VKTA, Dresden (Germany); Enghardt, W. [Technische Univ. Dresden (Germany). OncoRay

2016-07-01

The process of clearance of radioactive materials according to paragraph 29 StrlSchV contents the comparison of activity to mass and surface of the material. To avoid a borderless assessment of activity of activation it is often necessary to use combined measurement methods: For clearance of collimators of a medical proton accelerator (energy range up to 200 MeV) it needs to know the nuclide composition. The energetical and geometrical calibration was fixed by experiments. The clearance based on measurements of activity distribution, gammaspectroscopy verification of nuclide composition and gamma-counting detectors. Parts of medical electron-accelerators achieved its clearance by combination of abovementioned methods and in-situ-gammaspectroscopy. Activated und contaminated lead stones achieved its clearance by measurements of fluence, laboratory evaluation of samples, in-situ-gammaspectroscopy and wipe tests.

Examination of the renal function during the first half of pregnancy

International Nuclear Information System (INIS)

Voigt, R.; Stoll, W.

1980-01-01

The renal function of 25 women in the first half of pregnancy was examined by means of sequence scintigrams of the kidneys and by the results of 131 I-hippurate clearance. Up to the 17th week of pregnancy a continuous increase of the clearance equivalents existed. In comparison to non-pregnant women no important changes were observed on the right and on the left above both the ROI of the renal parenchyma and of the renal pelvis. Problems referring to the clearance of paraaminohippuric acid, which is tubularly excreted like 131 I-hippurate, were discussed. Despite of the good suitability of radionuclide methods for screening of the renal function, they should not be applied in early pregnancy because of radioprotective reasons

Polypharmacy and Renal Failure in Nursing Home Residents: Results of the Inappropriate Medication in Patients with Renal Insufficiency in Nursing Homes (IMREN) Study.

Science.gov (United States)

Dörks, Michael; Herget-Rosenthal, Stefan; Schmiemann, Guido; Hoffmann, Falk

2016-01-01

Polypharmacy has become an emerging public health issue in recent years, since use of multiple medications or polypharmacy is beneficial for many conditions, but may also have negative effects like adverse drug reactions. The risk further increases in patients with chronic renal failure, a comorbidity very frequent in nursing home residents. Since more than 50% of all drugs were renally excreted, dose adjustments in patients with renal failure are required. To assess polypharmacy in German nursing homes, in particular in residents with renal failure. Multi-center cross-sectional study in 21 nursing homes in Bremen and Lower Saxony/Germany. Baseline data were analysed using descriptive statistics. Multivariable logistic regression model and 95% confidence intervals were used to study the association of renal failure and polypharmacy. Of all 852 residents, the analysis comprised those 685 with at least one serum creatinine value so that the estimated creatinine clearance could be calculated. Of those, 436 (63.6%) had a severe or moderate renal failure, defined as estimated creatinine clearance renal failure (estimated creatinine clearance renal failure are common in German nursing home residents and an association of both could be found. Further studies are needed to assess the appropriateness of polypharmacy in these patients.

Nuclear medical investigations of renal transplants in dogs

International Nuclear Information System (INIS)

Chocholka, T.G.K.

1981-01-01

Within the frame of this study it was investigated if it is possible - by means of nuclear medicine - to assess transplant function after xenogenic (heterologic) renal transplantation, to early diagnose complications and to observe organ function in follow-up examinations. The examination comprised camera-function-scintiscanning (=CFS), i.e. camera-sequence-scintiscanning (=CSS) and radio-isotope-nephrography (=RING), and the clearance measurement, which were carried out in parallel, as one operation. The clearance measurement based on tissue activity decrease graphs, which were registered by means of a body probe. Hippuran iodine 131 was used as radiopharmaceutical which usually is eliminated by the kidneys. In 112 examinations 33 dogs, who had received a fox kidney transplant, were investigated, starting on the day of surgical intervention until the transplant dysfunction was confirmed. These dogs had been treated in advance with immunosuppressive agents: a control group of 8 dogs, who received renal transplants of dingos, were not treated with immunosuppressants. The CFS as simultaneous realisation of CSS and of RING and the clearance measurement by means of hippuran iodine 131 achieved the examination aims. CSS permitted a sufficient survey over the individual functional phases. RING allows the early diagnosis of complications due to transplantation. The nuclear medical findings of camera-functional-scintiscanning and of clearance measurement show correspondence and they correspond also well to those findings resulting from traditional examination techniques which were applied in parallel. This procedure distinguishes itself not only by the diagnostic liability of nuclear medical examination methods, but also by its uncomplicated application, which permits the careful treatment of the dogs. (orig./MG) [de

PGI2 synthesis and excretion in dog kidney: evidence for renal PG compartmentalization

International Nuclear Information System (INIS)

Boyd, R.M.; Nasjletti, A.; Heerdt, P.M.; Baer, P.G.

1986-01-01

To assess the concept of compartmentalization of renal prostaglandins (PG), we compared entry of PGE2 and the PGI2 metabolite 6-keto-PGF1 alpha into the renal vascular and tubular compartments, in sodium pentobarbital-anesthetized dogs. Renal arterial 6-keto-PGF1 alpha infusion increased both renal venous and urinary 6-keto-PGF1 alpha outflow. In contrast, renal arterial infusion of arachidonic acid (AA) or bradykinin (BK) increased renal venous 6-keto-PGF1 alpha outflow but had no effect on its urinary outflow. Both urinary and renal venous PGE2 outflows increased during AA or BK infusion. Ureteral stopped-flow studies revealed no postglomerular 6-keto-PGF1 alpha entry into tubular fluid. During renal arterial infusion of [3H]PGI2 and inulin, first-pass 3H clearance was 40% of inulin clearance; 35% of urinary 3H was 6-keto-PGF1 alpha, and two other urinary metabolites were found. During renal arterial infusion of [3H]6-keto-PGF1 alpha and inulin, first-pass 3H clearance was 150% of inulin clearance; 75% of urinary 3H was 6-keto-PGF1 alpha, and only one other metabolite was found. We conclude that in the dog PGE2 synthesized in the kidney enters directly into both the renal vascular and tubular compartments, but 6-keto-PGF1 alpha of renal origin enters directly into only the renal vascular compartment

Turbine blade tip clearance measurement using a skewed dual-beam fiber optic sensor

Science.gov (United States)

Ye, De-chao; Duan, Fa-jie; Guo, Hao-tian; Li, Yangzong; Wang, Kai

2012-08-01

Optimization and active control of the tip clearance of turbine blades has been identified as a key to improve fuel efficiency, reduce emission, and increase service life of the engine. However, reliable and real-time tip clearance measurement is difficult due to the adverse environmental conditions that are typically found in a turbine. We describe a dual-beam fiber optic measurement system that can measure the tip timing and tip clearance simultaneously. Because the tip timing information is used to calculate the tip clearance, the method is insensitive to the signal intensity variation caused by fluctuations in environmental conditions such as light source instability, contamination, and blade tip imperfection. The system was calibrated and tested using experimental rotors. The test results indicated a high resolution of 4.5 μm and measurement accuracy of ±20 μm over the rotation speed range of 2000 to 10,000 rpm.

Renal Extraction and Acute Effects of Glucagon-like peptide-1 on Central and Renal Hemodynamics in Healthy Men

DEFF Research Database (Denmark)

Asmar, Ali; Simonsen, Lene; Asmar, Meena

2015-01-01

of either GLP-1 (1.5 pmol kg-1 min-1) or saline, cardiac output was estimated non-invasively, and intra-arterial blood pressure and heart rate were measured continuously. Renal plasma flow, glomerular filtration rate, and uptake/release of hormones and ions were measured by Fick's Principle after...... catheterization of a renal vein. The subjects remained supine during the experiments. During GLP-1 infusion, the systolic blood pressure and arterial pulse pressure both increased by 5 ± 1 mm Hg (p=0.015 and p=0.002, respectively). Heart rate increased by 5 ± 1 bpm (p=0.005) and cardiac output increased by 18...... % (p=0.016). Renal plasma flow and glomerular filtration rate as well as clearance of sodium and lithium were not affected by GLP-1. However, plasma renin activity decreased (p=0.037), whereas plasma levels of atrial natriuretic peptide (ANP) were unaffected. Renal extraction of intact GLP-1 was 43% (p...

Standardization of a method to calculate absolute renal uptake of {sup 99m} Tc-DMSA in children; Padronizacao do metodo para calculo da captacao renal absoluta do {sup 99m}Tc-DMSA em criancas

Energy Technology Data Exchange (ETDEWEB)

Ono, Carla Rachel; Sapienza, Marcelo Tatit; Watanabe, Tomoco; Costa, Paulo Luiz Aguirre; Okamoto, Miriam Roseli Yoshie; Garcez, Alexandre Teles; Buchpiguel, Carlos Alberto [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Servico de Medicina Nuclear]. E-mail: crachelo@usp.br; Machado, Beatriz Marcondes; Machado, Marcia Melo Campos [Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital Universitario; Liberato Junior, Waldyr de Paula

2006-01-15

Objective:To standardize a method and determine normal values for absolute renal uptake of 99m Tc-DMSA in children with normal creatinine clearance. Materials and methods: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years) without clinical evidence of renal disease were studied using 99m Tc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99m Tc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance. Absolute renal uptake of 99m Tc-DMSA (DMSA-Abs) was expressed as the fraction of the administered dose retained by each kidney six hours after administration of the radiopharmaceutical. Results: DMSA-Abs was 21.8 +- 3.2% for the right kidney and 23.1 +-3.3% for the left kidney. There was no correlation between renal uptake and the age groups studied, although there was a tendency to an increase in the creatinine clearance with age. Conclusion: Normal values of DMSA-Abs can be used as an additional parameter for the initial diagnostic evaluation and during follow-up of renal diseases, mainly when bilateral impairment of renal function is suspected or in a patient with a single functioning kidney (in which renal differential function is of limited value). (author)

What method to use for the renal clearance with {sup 51}Cr-E.D.T.A.: retrospective study among 1157 adults and 286 children; Quelle methode de mesure utiliser pour la clairance renale au 51Cr-EDTA: etude retrospective chez 1157 adultes et 286 enfants

Energy Technology Data Exchange (ETDEWEB)

Lacoeuille, F.; Machefert, N.; Vervueren, L.; Berthelot, C.; Rakotonirina, H.; Le Jeune, J.J.; Couturier, O. [CHU d' Angers, Service de medecine nucleaire, 49 (France); Drablier, G.; Cahouet-Vannier, A. [CHU d' Angers, Service de pharmacie, 49 (France); Denizot, B. [CH Annemasse, service de medecine nucleaire, 74 (France)

2010-07-01

Purpose: in the objective to make our practices evolve and to limit the numbers of sampling for patients, we searched to determine if the methods used (4,2 or 1 sampling) to measure the renal clearance to {sup 51}Cr-EDTA give results comparable on the population of patients concerned by this examination. Conclusions: This study allowed to enlighten interchangeability between the four points and two points method for the population studied. It allows to consider a change in our practice for the profit of a two points methods. (N.C.)

Estimation of technetium 99m mercaptoacetyltriglycine plasma clearance by use of one single plasma sample

International Nuclear Information System (INIS)

Mueller-Suur, R.; Magnusson, G.; Karolinska Inst., Stockholm; Bois-Svensson, I.; Jansson, B.

1991-01-01

Recent studies have shown that technetium 99m mercaptoacetyltriglycine (MAG-3) is a suitable replacement for iodine 131 or 123 hippurate in gamma-camera renography. Also, the determination of its clearance is of value, since it correlates well with that of hippurate and thus may be an indirect measure of renal plasma flow. In order to simplify the clearance method we developed formulas for the estimation of plasma clearance of MAG-3 based on a single plasma sample and compared them with the multiple sample method based on 7 plasma samples. The correlation to effective renal plasma flow (ERPF) (according to Tauxe's method, using iodine 123 hippurate), which ranged from 75 to 654 ml/min per 1.73 m 2 , was determined in these patients. Using the developed regression equations the error of estimate for the simplified clearance method was acceptably low (18-14 ml/min), when the single plasma sample was taken 44-64 min post-injection. Formulas for different sampling times at 44, 48, 52, 56, 60 and 64 min are given, and we recommend 60 min as optimal, with an error of estimate of 15.5 ml/min. The correlation between the MAG-3 clearances and ERPF was high (r=0.90). Since normal values for MAG-3 clearance are not yet available, transformation to estimated ERPF values by the regression equation (ERPF=1.86xC MAG-3 +4.6) could be of clinical value in order to compare it with the normal values for ERPF given in the literature. (orig.)

Renal effects of chronic exposure to organic solvents. A clinical controlled trial

Energy Technology Data Exchange (ETDEWEB)

Krusell, L.; Nielsen, H.K.; Baelum, J.; Lundqvist, G.; Omland, O.; Vaeth, M.; Husted, S.E.; Mogensen, C.E.; Geday, E.

1985-01-01

Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin. This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers.

Renal effects of chronic exposure to organic solvents. A clinical controlled trial

DEFF Research Database (Denmark)

Krusell, Lars Romer; Nielsen, H K; Bælum, Jesper

1985-01-01

Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age......-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin....... This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers....

Evaluation of plasma clearance by synthesis of continuous infusion: principles and use

International Nuclear Information System (INIS)

Chonacky, N.J.; Thomas, F.D.

1986-01-01

There is a technique of engineering analysis which can be described as impulse synthesis which uses the observational data of a system's response to a single sharp blow in order to predict its response to a steady force. This same technique has been applied to the calculation of in situ drug levels and for calculating plasma clearance values. The purpose of this paper is to elucidate the principles of this calculation technique and to critically assess its application to plasma clearance studies. We begin by tracing the history of the measurement of renal clearance of plasma. We then proceed to exposit the relevant principles of the synthesis technique. Finally, we report the results of our application of this technique to the analysis of simulated data in a manner intended to be of use to clinicians who might wish to consider employing the technique

Measurement of renal blood flow by phase-contrast magnetic resonance imaging during septic acute kidney injury: a pilot investigation.

Science.gov (United States)

Prowle, John R; Molan, Maurice P; Hornsey, Emma; Bellomo, Rinaldo

2012-06-01

In septic patients, decreased renal perfusion is considered to play a major role in the pathogenesis of acute kidney injury. However, the accurate measurement of renal blood flow in such patients is problematic and invasive. We sought to overcome such obstacles by measuring renal blood flow in septic patients with acute kidney injury using cine phase-contrast magnetic resonance imaging. Pilot observational study. University-affiliated general adult intensive care unit. Ten adult patients with established septic acute kidney injury and 11 normal volunteers. Cine phase-contrast magnetic resonance imaging measurement of renal blood flow and cardiac output. The median age of the study patients was 62.5 yrs and eight were male. At the time of magnetic resonance imaging, eight patients were mechanically ventilated, nine were on continuous hemofiltration, and five required vasopressors. Cine phase-contrast magnetic resonance imaging examinations were carried out without complication. Median renal blood flow was 482 mL/min (range 335-1137) in septic acute kidney injury and 1260 mL/min (range 791-1750) in healthy controls (p = .003). Renal blood flow indexed to body surface area was 244 mL/min/m2 (range 165-662) in septic acute kidney injury and 525 mL/min/m2 (range 438-869) in controls (p = .004). In patients with septic acute kidney injury, median cardiac index was 3.5 L/min/m2 (range 1.6-8.7), and median renal fraction of cardiac output was only 7.1% (range 4.4-10.8). There was no rank correlation between renal blood flow index and creatinine clearance in patients with septic acute kidney injury (r = .26, p = .45). Cine phase-contrast magnetic resonance imaging can be used to noninvasively and safely assess renal perfusion during critical illness in man. Near-simultaneous accurate measurement of cardiac output enables organ blood flow to be assessed in the context of the global circulation. Renal blood flow seems consistently reduced as a fraction of cardiac output in

Lung mucociliary clearance

International Nuclear Information System (INIS)

Mortensen, J.; Lange, P.; Nyboe, J.; Groth, S.

1994-01-01

The aim of this study was to establish reference values for mucociliary clearance and mucociliary clearance reserve capacity as determined by β 2 -adrenergic agonist-induced increase in mucociliary clearance. We studied 62 healthy females (n=33) and males (n=29). Their ages ranged evenly between 18 and 84 years. Fifty-three of the subjects were life-long non-smokers, while nine were ex-smokers. Multiple linear regression analyses showed that mucociliary clearance was significantly faster when the radioaerosol was deposited in the central airways than when it was deposited in the peripheral airways, and faster in life-long non-smokers than in ex-smokers. There was no influence of age, and no convincing association with sex. The variation was less within than between subjects. Mean mucociliary clearance reserve capacity was 21.3% (SD: 10.0%, P 2 agonist-induced increase in lung mucociliary clearance was significantly larger (P<0.05) than the stimulation which has previously been reported in patients with asthma, bronchiectasis or cystic fibrosis. The signal-to-noise ratio of the mucociliary clearance reserve capacity in relation to measurement of baseline mucociliary clearance indicates that measurement of mucociliary clearance reserve capacity may be a more efficient means of distinguishing between ''normal'' and ''abnormal'' mucociliary clearance than single measurement of baseline mucociliary clearance. (orig.)

Glomerular filtration rate equations overestimate creatinine clearance in older individuals enrolled in the Baltimore Longitudinal Study on Aging: impact on renal drug dosing.

Science.gov (United States)

Dowling, Thomas C; Wang, En-Shih; Ferrucci, Luigi; Sorkin, John D

2013-09-01

To evaluate the performance of kidney function estimation equations and to determine the frequency of drug dose discordance in an older population. Cross-sectional analysis of data from community-dwelling volunteers randomly selected from the Baltimore Longitudinal Study of Aging from January 1, 2005, to December 31, 2010. A total of 269 men and women with a mean ± SD age of 81 ± 6 years, mean serum creatinine concentration (Scr ) of 1.1 ± 0.4 mg/dl, and mean 24-hour measured creatinine clearance (mClcr ) of 53 ± 13 ml/minute. Kidney function was estimated by using the following equations: Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI). The performance of each equation was assessed by measuring bias and precision relative to mClcr . Dose calculation errors (discordance) were determined for 10 drugs requiring renal dosage adjustments to avoid toxicity when compared with the dosages approved by the Food and Drug Administration. The CG equation was the least biased estimate of mClcr . The MDRD and CKD-EPI equations were significantly positively biased compared with CG (mean ± SD 34 ± 20% and 22 ± 15%, respectively, prenal impairment. Thus equations estimating glomerular filtration rate should not be substituted in place of the CG equation in older adults for the purpose of renal dosage adjustments. In addition, the common practice of rounding or replacing low Scr values with an arbitrary value of 1.0 mg/dl for use in the CG equation should be avoided. Additional studies that evaluate alternative eGFR equations in the older populations that incorporate pharmacokinetic and pharmacodynamic outcomes measures are needed. © 2013 Pharmacotherapy Publications, Inc.

Effect of selective inhibition of renal inducible nitric oxide synthase on renal blood flow and function in experimental hyperdynamic sepsis.

Science.gov (United States)

Ishikawa, Ken; Calzavacca, Paolo; Bellomo, Rinaldo; Bailey, Michael; May, Clive N

2012-08-01

Nitric oxide plays an important role in the control of renal blood flow and renal function. In sepsis, increased levels of inducible nitric oxide synthase produce excessive nitric oxide, which may contribute to the development of acute kidney injury. We, therefore, examined the effects of intrarenal infusion of selective inducible nitric oxide synthase inhibitors in a large animal model of hyperdynamic sepsis in which acute kidney injury occurs in the presence of increased renal blood flow. Prospective crossover randomized controlled interventional studies. University-affiliated research institute. Twelve unilaterally nephrectomized Merino ewes. Infusion of a selective (1400W) and a partially selective inducible nitric oxide synthase inhibitor (aminoguanidine) into the renal artery for 2 hrs after the induction of sepsis, and comparison with a nonselective inhibitor (Nω-nitro-L-arginine methyl ester). In sheep with nonhypotensive hyperdynamic sepsis, creatinine clearance halved (32 to 16 mL/min, ratio [95% confidence interval] 0.51 [0.28-0.92]) despite increased renal blood flow (241 to 343 mL/min, difference [95% confidence interval] 102 [78-126]). Infusion of 1400W did not change renal blood flow, urine output, or creatinine clearance, whereas infusion of Nω-nitro-L-arginine methyl ester and a high dose of aminoguanidine normalized renal blood flow, but did not alter creatinine clearance. In hyperdynamic sepsis, intrarenal infusion of a highly selective inducible nitric oxide synthase inhibitor did not reduce the elevated renal blood flow or improve renal function. In contrast, renal blood flow was reduced by infusion of a nonselective NOS inhibitor or a high dose of a partially selective inducible nitric oxide synthase inhibitor. The renal vasodilatation in septic acute kidney injury may be due to nitric oxide derived from the endothelial and neural isoforms of nitric oxide synthase, but their blockade did not restore renal function.

Prediction of cardiovascular outcome by estimated glomerular filtration rate and estimated creatinine clearance in the high-risk hypertension population of the VALUE trial.

Science.gov (United States)

Ruilope, Luis M; Zanchetti, Alberto; Julius, Stevo; McInnes, Gordon T; Segura, Julian; Stolt, Pelle; Hua, Tsushung A; Weber, Michael A; Jamerson, Ken

2007-07-01

Reduced renal function is predictive of poor cardiovascular outcomes but the predictive value of different measures of renal function is uncertain. We compared the value of estimated creatinine clearance, using the Cockcroft-Gault formula, with that of estimated glomerular filtration rate (GFR), using the Modification of Diet in Renal Disease (MDRD) formula, as predictors of cardiovascular outcome in 15 245 high-risk hypertensive participants in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial. For the primary end-point, the three secondary end-points and for all-cause death, outcomes were compared for individuals with baseline estimated creatinine clearance and estimated GFR or = 60 ml/min using hazard ratios and 95% confidence intervals. Coronary heart disease, left ventricular hypertrophy, age, sex and treatment effects were included as covariates in the model. For each end-point considered, the risk in individuals with poor renal function at baseline was greater than in those with better renal function. Estimated creatinine clearance (Cockcroft-Gault) was significantly predictive only of all-cause death [hazard ratio = 1.223, 95% confidence interval (CI) = 1.076-1.390; P = 0.0021] whereas estimated GFR was predictive of all outcomes except stroke. Hazard ratios (95% CIs) for estimated GFR were: primary cardiac end-point, 1.497 (1.332-1.682), P cause death, 1.231 (1.098-1.380), P = 0.0004. These results indicate that estimated glomerular filtration rate calculated with the MDRD formula is more informative than estimated creatinine clearance (Cockcroft-Gault) in the prediction of cardiovascular outcomes.

Measurement with nasal scintigraphy of nasal mucociliary clearance in normal man

International Nuclear Information System (INIS)

Murai, Sumiko

1989-01-01

Nasal mucociliary function was evaluated by nasal scintigraphy in normal subjects. A microdrop of HSA or saline labelled with 99m Tc was dripped into the middle part of each middle meatus in the nasal cavity and its clearance was observed by scinticamera. The accumulated concentration of RI was determined every 30 seconds for 10 minutes. The changes of accumulated concentration were studied, and a curve of decreasing RI-counts was obtained, with the 'clearance rate' defined as 100% for the count at the initial 30 seconds and 'half time' as the time when radioactivity was reduced to one half the initial count. Nasal resistance was measured by rhinomanometry with the oscillation method. In nonsmokers, 10μl of saline was cleared (78.0±10.4%) significantly faster than 10μl of HSA (59.9±24.6%), and there was no significant difference in the clearance between 10μl and 5μl of HSA (55.9±27.7%). In smakers, the mucociliary clearance of 10μl of HSA and saline was significantly lower than in nonsmokers. The clearance of 10μl of HSA reflects a pathological state much better than that of 5μl. In nonsmokers, there is a significant negative correlation between nasal resistance and clearance rate, suggesting that the more patent the nose, the faster the mucociliary clearance. When both nostrils were closed, the clearance rate was significantly depressed. When one nostril was closed, there was no significant effect on clearance. Nasal resistance was decreased by exercise with a bicycle ergometer. Nasal mucociliary clearance was slightly decreased after exercise but not significantly so. (J.P.N.)

Standardization of a method to calculate absolute renal uptake of 99m Tc-DMSA in children

International Nuclear Information System (INIS)

Ono, Carla Rachel; Sapienza, Marcelo Tatit; Watanabe, Tomoco; Costa, Paulo Luiz Aguirre; Okamoto, Miriam Roseli Yoshie; Garcez, Alexandre Teles; Buchpiguel, Carlos Alberto; Machado, Beatriz Marcondes; Machado, Marcia Melo Campos; Liberato Junior, Waldyr de Paula

2006-01-01

Objective:To standardize a method and determine normal values for absolute renal uptake of 99m Tc-DMSA in children with normal creatinine clearance. Materials and methods: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years) without clinical evidence of renal disease were studied using 99m Tc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99m Tc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance. Absolute renal uptake of 99m Tc-DMSA (DMSA-Abs) was expressed as the fraction of the administered dose retained by each kidney six hours after administration of the radiopharmaceutical. Results: DMSA-Abs was 21.8 +- 3.2% for the right kidney and 23.1 +-3.3% for the left kidney. There was no correlation between renal uptake and the age groups studied, although there was a tendency to an increase in the creatinine clearance with age. Conclusion: Normal values of DMSA-Abs can be used as an additional parameter for the initial diagnostic evaluation and during follow-up of renal diseases, mainly when bilateral impairment of renal function is suspected or in a patient with a single functioning kidney (in which renal differential function is of limited value). (author)

Simple technique for measuring relative renal blood flow

International Nuclear Information System (INIS)

Shames, D.M.; Korobkin, M.

1976-01-01

To determine whether externally monitored early renal uptake of 131 I-hippurate is proportional to renal blood flow, the renal uptake of 131 -hippurate at 1 to 2 min after injection was compared with the renal accumulation of radioactive carbonized microspheres in dogs. A renal artery catheter equipped with a balloon was used to decrease renal blood flow unilaterally. One minute after the intravenous injection of 100 μCi of 131 I-hippurate, about 1 μCi of either 85 Sr- or 95 Nb-labeled carbon microspheres was injected into the left ventricle. Radioactivity was measured over both kidneys. The total radioactivity within each kidney region of interest was corrected for background and integrated over the 1 to 2 min interval after injection. Thirteen measurements of relative renal blood flow were made for seven dogs. The dogs were then killed and both kidneys were excised and counted for the radioactivity of the microspheres. The 1 to 2-min relative renal uptake of 131 I-hippurate correlated well with relative microsphere uptake, suggesting that relative renal blood flow can be simply determined from the external measurements of renal uptake of 131 I-hippurate

Renal function and plasma dabigatran level measured at trough by diluted thrombin time assay

Directory of Open Access Journals (Sweden)

Marta E. Martinuzzo

2017-02-01

Full Text Available Dabigatran etexilate (direct thrombin inhibitor is effective in preventing embolic stroke in patients with atrial fibrillation. It does not require laboratory control, but given the high renal elimination, its measurement in plasma is important in renal failure. The objectives of the study were to verify the analytical quality of the diluted thrombin time assay for measurement of dabigatran plasma concentration (cc, correlate cc with classic coagulation assays, prothrombin time (PT and activated partial thromboplastin time (APTT, and evaluate them according to the creatinine clearance (CLCr. Forty plasma samples of patients (34 consecutive and 6 suspected of drug accumulation receiving dabigatran at 150 (n = 19 or 110 (n = 21 mg/12 hours were collected. Blood samples were drawn at 10-14 hours of the last intake. Dabigatran concentration was determined by diluted thrombin time (HemosIl DTI, Instrumentation Laboratory (IL. PT and APTT (IL were performed on two fotooptical coagulometers, ACL TOP 300 and 500 (IL. DTI presented intra-assay coefficient of variation < 5.4% and inter-assay < 6%, linearity range 0-493 ng/ml. Patients' cc: median 83 (4-945 ng/ml. Individuals with CLCr in the lowest tertile (22.6-46.1 ml/min showed significantly higher median cc: 308 (49-945, compared to the average 72 (12-190 and highest tertile, 60 (4-118 ng/ml. Correlation between cc and APTT or PT were moderate, r2 = 0.59 and -0.66, p < 0.0001, respectively. DTI test allowed us to quantify plasma dabigatran levels, both in patients with normal or altered renal function, representing a useful tool in clinical situations such as renal failure, pre surgery or emergencies

Accuracy and precision of the CKD-EPI and MDRD predictive equations compared with glomerular filtration rate measured by inulin clearance in a Saudi population.

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Al-Wakeel, Jamal Saleh

2016-01-01

Predictive equations for estimating glomerular filtration rate (GFR) in different clinical conditions should be validated by comparing with the measurement of GFR using inulin clearance, a highly accurate measure of GFR. Our aim was to validate the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations by comparing it to the GFR measured using inulin clearance in chronic kidney disease (CKD) patients. Cross-sectional study performed in adult Saudi patients with CKD. King Saud University Affiliated Hospital, Riyadh, Saudi Arabia in 2014. We compared GFR measured by inulin clearance with the estimated GFR calculated using CKD-EPI and MDRD predictive formulas. Correlation, bias, precision and accuracy between the estimated GFR and inulin clearance. Comparisons were made in 31 participants (23 CKD and 8 transplanted), including 19 males (mean age 42.2 [15] years and weight 68.7 [18] kg). GFR using inulin was 51.54 (33.8) mL/min/1.73 m2 in comparison to inulin clearance, the GFR by the predictive equations was: CKD-EPI creatinine 52.6 (34.4) mL/ min/1.73 m2 (P=.490), CKD-EPI cystatin C 41.39 (30.30) mL/min/1.73 m2 (P=.002), CKD creatinine-cystatin C 45.03 (30.9) mL/min/1.73 m2 (P=.004) and MDRD GFR 48.35 (31.5) mL/min/1.73 m2 (P=.028) (statistical comparisons vs inulin). Bland-Altman plots demonstrated that GFR estimated by the CKD-EPI creatinine was the most accurate compared with inulin clearance, having a mean difference (estimated bias) and limits of agreement of -1.1 (15.6,-17.7). By comparison the mean differences for predictive equations were: CKD-EPI cystatin C 10.2 (43.7,-23.4), CKD creatinine-cystatin C 6.5 (29.3,-16.3) and MDRD 3.2 (18.3,-11.9). except for CKD-EPI creatinine, all of the equations underestimated GFR in comparison with inulin clearance. When compared with inulin clearance, the CKD-EPI creatinine equation is the most accurate, precise and least biased equation for estimation of GFR

Proficiency testing criteria for clearance level in solid waste gamma measurement in Taiwan.

Science.gov (United States)

Chen, Chun-Liang; Wang, Jeng-Jong; Chiu, Huang-Sheng

2013-11-01

To guarantee the measurement quality for clearance level in solid waste material, the Institute of Nuclear Energy Research (INER) established the criteria for proficiency testing of clearance level measurement. INER and the Taiwan Accreditation Foundation (TAF) organized the Technique Committee Meeting twice to discuss these criteria in 2011. The participating laboratories must completely conform to the ISO/IEC 17025, and they also must meet the requirements of the criteria. According to the criteria, the participating laboratories analyzed the minimum detectable amount (MDA) and that should be less than 20% of the clearance level (AMDA) given in the Atomic Energy Council's (AEC) "Regulations on Clearance Level for Radioactive Waste Management". The testing results should conform to the deviation and traceability requirements. Copyright © 2013 Elsevier Ltd. All rights reserved.

A gamma camera method for quantitation of split renal function in children followed for vesicoureteric reflux

International Nuclear Information System (INIS)

Tamminen, T.E.; Riihimaeki, E.J.; Taehti, E.E.; Helsinki Univ. Central Hospital

1978-01-01

A method for quantitative estimation of split renal function using a computerized gamma camera system is described. 42 children and adolescents with existing or preexisting vesicouretric reflux and recurrent urinary tract infection were investigated. Total renal clearance of DTPA was calculated with a disapperarance curve derived from the largest extrarenal area in the field of view of a gamma camera with diverging collimator. Split renal function was estimated with the slopes of second phase renograms. The plasma disaapearance clearance of DTPA, calculated using one compartement model with two late blood samples, gave similar resusults with the clearance estimated from the body disappearance curves. The proportional planimetric renal parenchymal areas had good correlation with the split clearance estimated from renogram slopes. The method offers data on renal function and urinary tract dynamics which is very valuable in the follow-up of children with recurrent urinary tract infection and vesicoureteric reflux. (orig.) [de

The effects of acebutolol and atenolol on renal function in patients with chronic renal failure and hypertension

International Nuclear Information System (INIS)

Lustig, A.

1985-03-01

The present study determined the effects of chronic administration of acebutolol and atenolol on renal function 22 patients suffering from chronic renal failure (mean GFR of 33.7 +- 4.0 ml/min) and hypertension. Renal function and systemic haemodynamics were measured after 2 weeks of placebo treatment, after 6 weeks of oral acebutolol therapy (200 - 400 mg/day) and after 6 weeks of atenolol therapy (50 - 100 mg/day). The GFR assessed by 51 Cr EDTA clearance fell by 9.4 +- 7.4% on acebutolol therapy and 7.9 +- 7.0% on atenolol therapy. The renal blood flow assessed by 131 I-Hippuran clearance increased by 18.1 +- 6.1% on atenolol (P 0.05). Blood urea rose significantly on both agents. Both agents were found to be effective in reducing the mean arterial pressure in the supine or in the standing positions. No significant differences were found regarding their effects on renal function. Atenolol was more effective than acebutolol in reducing the heart rate. Plasma drug levels were measured. The combined levels of acebutolol and diacetolol were in the recommended therapeutic window (0.2 - 2.0 μg/ml) in 16 patients receiving acebutolol and in excess of this in 5 patients. Atenolol levels were in the recommended therapeutic window (0.1 - 1.0 μg/ml) in 10 patients and in excess of this in 10 patients. The alterations in the various parameters induced by the beta blockers in patients with GFR of less than 30 ml/min were similar to those induced in the patients who had GFR of over 30 ml/min. In conclusion: despite effective drop of blood pressure and heart rate induced by acebutolol and atenolol, these agents did not reduce the RBF and the fall in GFR noted was small magnitude and of no clinical significance. These two beta blockers may be used in patients with CRF provided caution is exercised and renal function is monitored regularly

Is the gravity effect of radiographic anatomic features enough to justify stone clearance or fragments retention following extracorporeal shock wave lithotripsy (SWL).

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Mustafa, Mahmoud

2012-08-01

We determined whether the gravity effect of radiographic anatomic features on the preoperative urography (IVP) are enough to predict fragments clearance after shock wave lithotripsy (SWL). A Total of 282 patients with mean age 45.8 ± 13.2 years (189 male, 93 female), who underwent SWL due to renal calculi between October 2005 and August 2009 were enrolled. The mean calculi load was 155.72 ± 127.66 mm². The patients were stratified into three groups: patients with pelvis calculi (group 1); patients with upper or middle pole calculi (group 2) and patients with lower pole calculi (group 3). Three angles on the pretreatment IVP were measured: the inner angle between the axis of the lower pole infundibular and ureteropelvic axis (angle I); the inner angle between the lower pole infundibular axis and main axis of pelvis-ureteropelvic (UP) junction point (angle II) and the inner angle between the lower pole infundibular axis and perpendicular line (angle III). Multivariate analysis was used to define the significant predictors of stone clearance. The overall success rate was 85.81%. All angles, sessions number, shock waves number and stone burden were significant predictors of success in patients in group 1. However, in group 2 only angle II and in group 3 angles I and II had significant effect on stone clearance. Radiographic anatomic features have significant role in determining the stone-free rate following satisfactory fragmentation of renal stones with SWL. The measurement of infundibulopelvic angle in different manner helps to predict the stone-free status in patients with renal calculi located not only in lower pole, but also in renal pelvis and upper or middle pole. Gravity effect is not enough to justify the significant influence of the radiographic anatomic features on the stone clearance and fragments retention after SWL.

Turbo machine tip clearance and vibration measurements using a fibre optic laser Doppler position sensor

Science.gov (United States)

Pfister, T.; Büttner, L.; Czarske, J.; Krain, H.; Schodl, R.

2006-07-01

This paper presents a novel fibre optic laser Doppler position sensor for single blade tip clearance and vibration measurements at turbo machines, which offers high temporal resolution and high position resolution simultaneously. The sensor principle is based on the generation of a measurement volume consisting of two superposed fan-like interference fringe systems with contrary fringe spacing gradients using wavelength division multiplexing. A flexible and robust measurement system with an all-passive fibre coupled measurement head has been realized employing diffractive and refractive optics. Measurements of tip clearance and rotor vibrations at a transonic centrifugal compressor performed during operation at up to 50 000 rpm (833 Hz) corresponding to 21.7 kHz blade frequency and 586 m s-1 blade tip velocity are presented. The results are in excellent agreement with those of capacitive probes. The mean uncertainty of the position measurement was around 20 µm and, thus, considerably better than for conventional tip clearance probes. Consequently, this sensor is capable of fulfilling the requirements for future active clearance control systems and has great potential for in situ and online tip clearance and vibration measurements at metallic and non-metallic turbine blades with high precision.

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

Frequency and causes of discrepancy between Kt/V and creatinine clearance.

Science.gov (United States)

Satko, S G; Burkart, J M; Bleyer, A J; Jordan, J R; Manning, T

1999-01-01

This study examines the frequency of discrepancy between Kt/V urea and creatinine clearance (Ccr) measurements in patients on peritoneal dialysis (PD) and the reasons for this discrepancy. Nonrandomized, retrospective data analysis. Single PD unit of a university teaching hospital. All adult patients receiving PD at our center from January 1995 to December 1996. Actual (a) and desired (d) body weight (BW) were used to calculate urea volume of distribution (V) and body surface area (BSA). Patients were divided into four groups based upon their total small solute clearances (Kt/V and Ccr, normalized by actual weight) and three additional groups based upon actual/desired (a/d) body weight ratio. An additional analysis was performed for the subset of anuric patients. Data collected for all patients included the following: total Kt, total Ccr, 4-hour dialysate/ plasma (D/P) creatinine, serum albumin concentration, duration of PD, actual body weight, age, and height. Twenty-three percent of the clearance measurements in our study were discrepant, defined as having values for either Kt/V or Ccr (but not both) above the accepted targets of Kt/V > or = 2.0/wk and Ccr > or = 60 L/wk/ 1.73 m2. Patients with both values above target are more likely to have higher residual renal function. Patients who are significantly less than BWd and patients on PD for a longer time are more likely to have adequate Kt/V but not Ccr. Furthermore, patients who are less than 90% or greater than 110% of BWd have markedly different values for Kt/V and Ccr when BWa versus BWd values are used. Kt/V and Ccr values are frequently discrepant; a number of factors affect these two measurements to varying degrees, including weight, degree of residual renal function, and duration of PD.

Hydrogen clearance: Assessment of technique for measurement of skin-flap blood flow in pigs

International Nuclear Information System (INIS)

Thomson, J.G.; Kerrigan, C.L.

1991-01-01

The hydrogen clearance technique has been used for many years by investigators to determine brain blood flow and has been partially validated in this setting using other methods of blood flow measurement. The method has been modified to allow blood flow measurements in skin, but the accuracy of H2 clearance for measuring skin blood flow has not been determined. Multiple blood flow measurements were performed using H2 clearance and radioactive microspheres on skin flaps and control skin in pigs. On 12 pigs, a total of 117 flap and 42 control skin measurements were available for analysis. There was no significant difference between the two techniques in measuring mean control skin blood flow. In skin flaps, H2 clearance was significantly correlated to microsphere-measured blood flow, but it consistently gave an overestimate. Sources of error may include injury to the tissues by insertion of electrodes, consumption of H2 by the electrodes, or diffusion of H2 from the relatively ischemic flap to its well-vascularized bed. Further studies are necessary to determine the cause of this error and to measure the technique's accuracy in skeletal muscle and other flaps

[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.

Contrast media and glomerular filtration: dose dependence of clearance for three agents

International Nuclear Information System (INIS)

Baeck, S.E.K.; Krutzen, E.; Nilsson-Ehle, P.

1988-01-01

Determination of plasma clearance of contrast agents has been advocated as a means to assess glomerular filtration rate. To evaluate the feasibility of different agents for this purpose, we have compared, in healthy volunteers, the dose dependence of plasma clearance for three contrast media (iohexol, a nonionic agent, and iothalamate and metrizoate, which are ionic substances), with special emphasis on the lower dose range (2-20 mL corresponding to 0.9-12.9 g, depending on dose and agent). Iohexol and iothalamate were cleared at constant rates, irrespective of given dose, whereas metrizoate clearance increased significantly at lower doses. In general, the clearances or iothalamate and metrizoate were, respectively, moderately and markedly higher than that of iohexol. The clearance of different doses of metrizoate (2 mL versus a radiographic dose of 40 mL or more) was also compared with the clearance of [ 51 Cr]EDTA in two groups of patients with reduced renal function. When compared with [ 51 Cr]EDTA in patients with renal dysfunction, metrizoate was cleared significantly faster after a 2-mL dose, whereas clearances were identical when the metrizoate dose was 40 mL or more. These findings indicate that tubular secretion plays an active role in the elimination of metrizoate. The pharmacokinetic properties of iohexol, in combination with its low toxicity, make it a suitable agent for determination of glomerular filtration rate in clinical practice

Renal volume assessed by magnetic resonance imaging volumetry correlates with renal function in living kidney donors pre- and postdonation: a retrospective cohort study.

Science.gov (United States)

Lange, Daniel; Helck, Andreas; Rominger, Axel; Crispin, Alexander; Meiser, Bruno; Werner, Jens; Fischereder, Michael; Stangl, Manfred; Habicht, Antje

2018-07-01

Renal function of potential living kidney donors is routinely assessed with scintigraphy. Kidney anatomy is evaluated by imaging techniques such as magnetic resonance imaging (MRI). We evaluated if a MRI-based renal volumetry is a good predictor of kidney function pre- and postdonation. We retrospectively analyzed the renal volume (RV) in a MRI of 100 living kidney donors. RV was correlated with the tubular excretion rate (TER) of MAG3-scintigraphy, a measured creatinine clearance (CrCl), and the estimated glomerular filtration rate (eGFR) by Cockcroft-Gault (CG), CKD-EPI, and modification of diet in renal disease (MDRD) formula pre- and postdonation during a follow-up of 3 years. RV correlated significantly with the TER (total: r = 0.6735, P volumetry might be an alternative technique for the evaluation of split renal function and prediction of renal function postdonation in living kidney donors. © 2018 Steunstichting ESOT.

Current status and methodological aspects on the measurement of glomerular filtration rate

International Nuclear Information System (INIS)

Froissart, M.; Hignette, C.; Kolar, P.; Prigent, A.; Paillard, M.

1995-01-01

Determination of the glomerular filtration rate (GFR) contribute to our understanding of kidney physiology and pathophysiology . Moreover, determination of GFR is of clinical importance in assessing the diagnosis and the progression of renal disease. The purpose of this article is to review the technical performance and results of GFR measurements, including the classical inulin clearance technique and more recent alternative clearance techniques using radioisotope-labelled filtration markers, bolus infusion and spontaneous bladder emptying. Some simplified techniques avoiding urinary collection are also described. We conclude that estimation of GFR from renal and in some cases plasmatic clearances is accurate and more convenient than the classical inulin clearance technique. Such measurements of GFR should be included both in clinical practice and clinical research. (authors). 80 refs., 5 figs., 1 tab

Measuring Clearance Mechanics Based on Dynamic Leg Length

Science.gov (United States)

Khamis, Sam; Danino, Barry; Hayek, Shlomo; Carmeli, Eli

2018-01-01

The aim of this study was to quantify clearance mechanics during gait. Seventeen children diagnosed with hemiplegic cerebral palsy underwent a three-dimensional gait analysis evaluation. Dynamic leg lengths were measured from the hip joint center to the heel, to the ankle joint center and to the forefoot throughout the gait cycle. Significant…

Proposal on new formulas for renal depth in the technetium-99m-mercaptoacetyltriglycine (MAG3) scintigraphy

International Nuclear Information System (INIS)

Uchiyama, Katsuhiro; Kuniyasu, Yoshio; Niio, Yasuo

1997-01-01

Recently, camera-based techniques to measure effective renal plasma flow (ERPF) have become more popular than single plasma sample techniques because camera-based measurements avoid the necessity of delayed plasma samples and in vitro techniques. The measurements of ERPF are used to estimate the clearance of technetium-99m-mercaptoacetyltriglycine (MAG3). However, camera-based techniques are dependent on an accurate estimate of renal depth to correct for soft-tissue attenuation. Then, new formulas for renal depth correction of technetium-99m-MAG3 clearance in place of Toennesen's, M. Ito's, K. Itoh's, and Taylor's methods were tried to establish in this paper. Eleven hundred and seventy patients without any renal disease were objected. The data from measurement of renal depth using X-ray CT in supine position were analyzed statistically. The depths of right kidney (Dr) and left kidney (Dl) were 7.33±1.27 and 7.07±1.27 cm. The correlation coefficients between Dr and height (H), body weight (W), body Surface area (BSA: W 0.425 xH 0.725 x0.007184 m 2 ), age, and abdominal thickness (Ta) were 0.275, 0.709, 0.615, 0.087, and 0.743. The correlation coefficients between Dl and H, W, BSA, age, and Ta were 0.269, 0.732, 0.629, 0.029, and 0.812. Ta had best correlation with both Dr and Dl. The calculation formulas for Dr and Dl using Ta were as follows; Dr=0.32xTa+0.87 cm, and Dl=0.36xTa-0.08 cm. On the other hand, the multiplex calculation formulas of Dr or Dl with H, W, and Ta were as follows; Dr=0.18Ta+8.54x(W/H)+0.75 (r=0.768), and Dl=0.26Ta+5.90x(W/H)-0.16 (r=0.823). The new regression equations provide superior estimates of renal depth compared to conventional equations. Application of these new formulas into camera-based protocols to determine renal clearances may lead to more accurate measurements of ERPF using technetium-99m-MAG3 scintigraphy. (author)

Well Preserved Renal Function in Children With Untreated Chronic Liver Disease.

Science.gov (United States)

Berg, Ulla B; Németh, Antal

2018-04-01

On the basis of studies with hepatorenal syndrome, it is widely regarded that renal function is impacted in chronic liver disease (CLD). Therefore, we investigated renal function in children with CLD. In a retrospective study of 277 children with CLD, renal function was investigated as glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), measured as clearance of inulin and para-amino hippuric acid or clearance of iohexol. The data were analyzed with regard to different subgroups of liver disease and to the grade of damage. Hyperfiltration (>+2 SD of controls) was found in the subgroups of progressive familial intrahepatic cholestasis (44%), glycogenosis (75%), and acute fulminant liver failure (60%). Patients with biliary atresia, most other patients with metabolic disease and intrahepatic cholestasis, and those with vascular anomalies and cryptogenic cirrhosis had normal renal function. Decreased renal function was found in patients with Alagille's syndrome (64% < -2 SD). Increased GFR and ERPF was found in patients with elevated transaminases, low prothrombin level, high bile acid concentration, and high aspartate-aminotransferase-to-platelet ratio. Most children with CLD had surprisingly well preserved renal function and certain groups had even hyperfiltration. The finding that children with decompensated liver disease and ongoing liver failure had stable kidney function suggests that no prognostic markers of threatening hepatorenal syndrome were at hand. Moreover, estimation of GFR based on serum creatinine fails to reveal hyperfiltration.

Bone blood flow measured by 41Ar clearance formed by 44Ca(n,α)41Ar

International Nuclear Information System (INIS)

Rosenthal, M.S.; DeLuca, P.M. Jr.; Pearson, D.W.; Nickles, R.J.

1983-01-01

A technique to measure regional inert gas washout in bone, in vivo, by measuring 41 Ar clearance formed by fast-neutron activation of 44 Ca has been developed. Following fast-neutron irradiation of whole rats, the perfusion-limited clearance of 41 Ar was measured for both dead and living rats. The clearance rate for the live rats indicate that the bone perfusion is in the range of 3 to 20 ml/100 Argon distribution volume

Quantitative renal cinescintigraphy with iodine-123 hippuran methodological aspects, kit for labeling of hippuran

International Nuclear Information System (INIS)

Mehdaoui, A.; Pecking, A.; Delorme, G.; Mathonnat, F.; Debaud, B.; Bardy, A.; Coornaert, S.; Merlin, L.; Vinot, J.M.; Desgrez, A.; Gambini, D.; Vernejoul, P. de.

1981-08-01

The development of an extemporaneous kit for the labeling of ortho-iodo-hippuric acid (Hippuran) with iodine 123 allows the performance of a routine quantitative renal cinescintigraphy providing in 20 minutes, and in an absolutely non-traumatic way, a very complete renal morphofunctional study including: a cortical renal scintigraphy, sequential scintigraphies of excretory tract, renal functional curves, tubular, global, and separate clearances for each kidney. This functional quantitative investigation method should take a preferential place in the routine renal balance. The methodology of the technique is explained and compared to classical methods for estimation of tubular, global and separate clearances [fr

The impact of intrarenal nitric oxide synthase inhibition on renal blood flow and function in mild and severe hyperdynamic sepsis.

Science.gov (United States)

Ishikawa, Ken; Bellomo, Rinaldo; May, Clive N

2011-04-01

In experimental hyperdynamic sepsis, renal function deteriorates despite renal vasodilatation and increased renal blood flow. Because nitric oxide is increased in sepsis and participates in renal blood flow control, we investigated the effects of intrarenal Nω-nitro-L-arginine methyl ester, a nonspecific nitric oxide synthase inhibitor, in mild and severe sepsis. Prospective crossover and randomized control interventional studies. University-affiliated research institute. Thirty-two merino ewes. Examination of responses to intrarenal infusion of Nω-nitro-L-arginine methyl ester for 8 hrs in unilaterally nephrectomized normal sheep and in sheep administered Escherichia coli. : In normal sheep, Nω-nitro-L-arginine methyl ester decreased renal blood flow (301 ± 30 to 228 ± 26 mL/min) and creatinine clearance (40.0 ± 5.8 to 31.1 ± 2.8 mL/min), whereas plasma creatinine increased, but fractional excretion of sodium was unchanged. In sheep with nonhypotensive hyperdynamic sepsis, plasma creatinine increased and there were decreases in creatinine clearance (34.5 ± 4.6 to 20.1 ± 3.7 mL/min) and fractional excretion of sodium despite increased renal blood flow. Infusion of Nω-nitro-L-arginine methyl ester normalized renal blood flow and increased urine output, but creatinine clearance did not improve and plasma creatinine and fractional excretion of sodium increased. In sheep with severe hypotensive sepsis, creatinine clearance decreased further (31.1 ± 5.4 to 16.0 ± 1.7 mL/min) despite increased renal blood flow. Infusion of Nω-nitro-L-arginine methyl ester restored mean arterial pressure and reduced renal blood flow but did not improve plasma creatinine or creatinine clearance. In hyperdynamic sepsis, with or without hypotension, creatinine clearance decreased despite increasing renal blood flow. Intrarenal Nω-nitro-L-arginine methyl ester infusion reduced renal blood flow but did not improve creatinine clearance. These data indicate that septic acute kidney

Pleural liquid clearance rate measured in awake sheep by the volume of dilution method

International Nuclear Information System (INIS)

Broaddus, V.C.; Wiener-Kronish, J.P.; Berthiaume, Y.; Staub, N.C.

1986-01-01

The authors reported 24h clearance of mock pleural effusions measured terminally in sheep. To measure effusion volume at different times in the same sheep, they injected 111 In-transferrin and measured its dilution. In 5 sheep with effusions of known sizes, the method was accurate to +/-10%. In 5 awake sheep, the authors injected 10 ml/kg of a 1% protein solution via a non-penetrating rib capsule. At 6h, the authors measured the volume by the dilution method and at 24h by direct recovery. The clearance rate in each animal was constant at 2.9-6.0%/h (average 4.8 +/- 1.3%/h). This new method gives a reliable two point clearance rate and requires fewer animals

Development of a liquid chromatography tandem mass spectrometry method for iothalamate measurement to assess renal function for potential kidney donation.

Science.gov (United States)

Rhea, Jeanne M; Ritchie, James C; Molinaro, Ross J

2013-05-01

Chronic kidney disease often goes undetected due to the insensitivity of current methods to accurately assess glomerular filtration rate (GFR) in early stages of renal dysfunction. The clearance of exogenously introduced iothalamate, a commonly used radiopaque agent, is an alternative to inulin clearance for the assessment of renal function and its use in calculating GFR can serve as a screening tool for kidney transplant donors. A method was developed to measure iothalamate in plasma and urine samples by HPLC combined with electrospray positive ionization tandem mass spectrometry (MS/MS). Iothalamate is isolated from plasma by methanol extraction and urine using a quick-spin filtration approach, then monitored by multiple reaction monitoring using the hydrogen adduct mass transitions. Iohexol was used as an internal standard. Iothalamate was measured within an analytical run time of 5 min, with a lower limit of quantification of 18.75 ng/ml. The intraassay and interassay variations of the plasma and urine iothalamate assays were both calculated using the patient's urine flow rate and plasma and urine iothalamate values. Linear correlations tested by LC-MS/MS and an accepted capillary electrophoresis (CE) assay showed similar results (GFR, r=0.92, Sy/x=10.3). We developed and validated an LC-MS/MS method for quantitating iothalamate in plasma and urine to calculate GFR used for screening potential kidney donors in our hospital system. A less sensitive mass spectrometry system does not sacrifice analytical or clinical sensitivity for measuring GFR. Copyright © 2012 Elsevier B.V. All rights reserved.

Creatinine Clearance Is Not Equal to Glomerular Filtration Rate and Cockcroft-Gault Equation Is Not Equal to CKD-EPI Collaboration Equation.

Science.gov (United States)

Fernandez-Prado, Raul; Castillo-Rodriguez, Esmeralda; Velez-Arribas, Fernando Javier; Gracia-Iguacel, Carolina; Ortiz, Alberto

2016-12-01

Direct oral anticoagulants (DOACs) may require dose reduction or avoidance when glomerular filtration rate is low. However, glomerular filtration rate is not usually measured in routine clinical practice. Rather, equations that incorporate different variables use serum creatinine to estimate either creatinine clearance in mL/min or glomerular filtration rate in mL/min/1.73 m 2 . The Cockcroft-Gault equation estimates creatinine clearance and incorporates weight into the equation. By contrast, the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations estimate glomerular filtration rate and incorporate ethnicity but not weight. As a result, an individual patient may have very different renal function estimates, depending on the equation used. We now highlight these differences and discuss the impact on routine clinical care for anticoagulation to prevent embolization in atrial fibrillation. Pivotal DOAC clinical trials used creatinine clearance as a criterion for patient enrollment, and dose adjustment and Federal Drug Administration recommendations are based on creatinine clearance. However, clinical biochemistry laboratories provide CKD-EPI glomerular filtration rate estimations, resulting in discrepancies between clinical trial and routine use of the drugs. Copyright © 2016 Elsevier Inc. All rights reserved.

Is Tamsulosin Effective after Shock Wave Lithotripsy for Pediatric Renal Stones? A Randomized, Controlled Study.

Science.gov (United States)

Shahat, Ahmed; Elderwy, Ahmad; Safwat, Ahmed S; Abdelkawi, Islam F; Reda, Ahmed; Abdelsalam, Yasser; Sayed, Mohamed; Hammouda, Hisham

2016-04-01

We assessed the effect of tamsulosin as an adjunctive therapy after shock wave lithotripsy for pediatric single renal pelvic stones. A total of 120 children with a unilateral single renal pelvic stone were included in a prospective randomized, controlled study. All children were randomized to 2 equal groups. Group 1 received tamsulosin (0.01 mg/kg once daily) as adjunctive therapy after shock wave lithotripsy in addition to paracetamol while group 2 received paracetamol only. Stone clearance was defined as no renal stone fragments or fragments less than 3 mm and no pelvicalyceal system dilatation. Our study included 69 boys and 51 girls with a median age of 3.5 years and a median stone size of 1.2 cm. There was no statistically significant difference between groups 1 and 2 in stone or patient criteria. Of the children 99 (82.5%) achieved stone clearance after the first session, including 50 in group 1 and 49 in group 2. All children in each group were cleared of stones after the second session. The overall complication rate was 14.2%. There was no statistically significant difference between single session stone clearance rates (p = 0.81) and complications rates (p = 0.432) in either group. On multivariate analysis using logistic regression smaller stone size (p = 0.016) and radiopaque stones (p = 0.019) were the only predictors of stone clearance at a single shock wave lithotripsy session. Tamsulosin therapy did not affect stone clearance (p = 0.649). Tamsulosin does not seem to improve renal stone clearance. Smaller and radiopaque renal stones have more chance of clearance after shock wave lithotripsy for pediatric single renal pelvic stones. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Aging aggravates long-term renal ischemia-reperfusion injury in a rat model.

Science.gov (United States)

Xu, Xianlin; Fan, Min; He, Xiaozhou; Liu, Jipu; Qin, Jiandi; Ye, Jianan

2014-03-01

Ischemia-reperfusion injury (IRI) has been considered as the major cause of acute kidney injury and can result in poor long-term graft function. Functional recovery after IRI is impaired in the elderly. In the present study, we aimed to compare kidney morphology, function, oxidative stress, inflammation, and development of renal fibrosis in young and aged rats after renal IRI. Rat models of warm renal IRI were established by clamping left pedicles for 45 min after right nephrectomy, then the clamp was removed, and kidneys were reperfused for up to 12 wk. Biochemical and histologic renal damage were assessed at 12 wk after reperfusion. The immunohistochemical staining of monocyte macrophage antigen-1 (ED-1) and transforming growth factor beta 1 (TGF-β1) and messenger RNA level of TGF-β1 in the kidney were analyzed. Renal IRI caused significant increases of malondialdehyde and 8-hydroxydeoxyguanosine levels and a decrease of superoxide dismutase activity in young and aged IRI rats; however, these changes were more obvious in the aged rats. IRI resulted in severe inflammation and tubulointerstitial fibrosis with decreased creatinine (Cr) clearance and increased histologic damage in aged rats compared with young rats. Moreover, we measured the ratio of Cr clearance between young and aged IRI rats. It demonstrated that aged IRI rats did have poor Cr clearance compared with the young IRI rats. ED-1 and TGF-β1 expression levels in the kidney were significantly higher in aged rats than in young rats after IRI. Aged rats are more susceptible to IRI-induced renal failure, which may associate with the increased oxidative stress, increased histologic damage, and increased inflammation and tubulointerstitial fibrosis. Targeting oxidative stress and inflammatory response should improve the kidney recovery after IRI. Copyright © 2014 Elsevier Inc. All rights reserved.

Clearance of Tc-99m DTPA in hemodialysis and peritoneal dialysis: concise communication

International Nuclear Information System (INIS)

Wainer, E.; Boner, G.; Lubin, E.; Rosenfeld, J.B.

1981-01-01

The clearance of Tc-99m DTPA was studied in 14 patients undergoing hemodialysis (HD) or peritoneal dialysis (PD). Mean Tc-99m DTPA clearance during HD was 37.8% +/- 10.1 of creatinine clearance. Mean Tc-99m DTPA clearance in PD was 65.1% +/- 10.3 of creatinine clearance. Tc-99m DTPA, with a larger molecular weight than that of creatinine, is cleared relatively better during PD than during HD. Thus Tc-99m DTPA may be used in the assessment of the effectiveness of different dialytic treatments for substances of similar molecular weight. In addition, our study shows that clearance of DTPA both in HD and PD is sufficiently high to allow the removal of this chelating agent in patients with renal failure

Determining vancomycin clearance in an overweight and obese population.

Science.gov (United States)

Leong, Julie V B; Boro, Maureen S; Winter, Michaele

2011-04-01

Two methods of calculating vancomycin clearance were compared to determine the best body weight measure to use when dosing vancomycin for overweight and obese patients. Hospitalized veterans weighing more than 120% of their ideal body weight (IBW) with serum vancomycin concentrations (SVCs) drawn between January 1, 2003, and June 30, 2005, were eligible for study inclusion. Exclusion criteria included weight of more than 300% the IBW, unstable renal function, dialysis, uncertain vancomycin dosing or sampling times, and distribution-phase sampling. Data from January 1 through December 31, 2003 (phase 1) determined the best-fit weight for vancomycin clearance for the Leonard and Boro method. The bias and precision of the modified Leonard and Boro method using the best-fit weight for vancomycin clearance were then compared with those of the Rushing and Ambrose method for predicting SVCs from January 1, 2004, through June 30, 2005 (phase 2). Forty-eight patients were included in phase 1, with 67 SVCs for analysis. During phase 1, adjusted body weight (ABW), using the Leonard and Boro method, was superior in predicting vancomycin clearance and the resultant SVCs. A total of 96 patients were included in phase 2 of the study, with 160 SVCs for analysis. The modified Leonard and Boro method was significantly more precise than the Rushing and Ambrose method in predicting vancomycin clearance. Use of ABW proved to be superior compared with total body weight when estimating vancomycin clearance in overweight and obese patients. While there was no difference in bias between methods, the modified Leonard and Boro method was significantly more precise than the Rushing and Ambrose method in predicting SVCs when dosing vancomycin for obese patients.

Changes in glomerular filtration rate, lithium clearance and plasma protein clearances in the early phase after unilateral nephrectomy in living healthy renal transplant donors

DEFF Research Database (Denmark)

Strandgaard, S; Kamper, A; Skaarup, P

1988-01-01

1. Glomerular and tubular function was studied before and 2 months after unilateral nephrectomy in 14 healthy kidney donors by measurement of the clearances of 51Cr-labelled ethylenediaminetetra-acetate, lithium, beta 2-microglobulin, albumin and immunoglobulin G. 2. The glomerular filtration rat...

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

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

Energy Technology Data Exchange (ETDEWEB)

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.)

Early experience with repeated determinations of 131-I-hipuran clearance-equivalent during pregnancy

Energy Technology Data Exchange (ETDEWEB)

Voigt, R; Stoll, W; Arndt, J

1981-07-01

Serial observations of ureteric and renal function during pregnancy were carried out by using isotope clearances; renal scintigraphy was performed for the first examination and isotope nephrography subsequently. The results of both types of examination are tabulated. It is shown that these procedures provide the necessary information on renal and ureteric function, given the indications which we have listed. The information concerns both kidneys or can be confined to a single kidney.

The renal handling of sodium and water is not affected by the standard-dose cisplatin treatment for testicular cancer

DEFF Research Database (Denmark)

Daugaard, G; Strandgaard, S; Holstein-Rathlou, N H

1987-01-01

Renal clearances of 51Cr-EDTA, lithium, sodium and potassium were measured before and after each of four consecutive treatment series with cisplatin in 15 men with testicular cancer. Since lithium is reabsorbed like sodium and water in the proximal tubules, but not reabsorbed to any measurable...... and all other parameters of glomerular filtration and renal sodium handling remained normal throughout the study (with the exception of a fall in fractional sodium excretion after the first treatment series). Plasma magnesium declined during all four treatment periods, signifying renal magnesium wasting....

Preoperative percutaneous transhepatic internal drainage in obstructive jaundice: a randomized, controlled trial examining renal function.

Science.gov (United States)

Smith, R C; Pooley, M; George, C R; Faithful, G R

1985-06-01

Thirty patients with obstructive jaundice with plasma bilirubin values greater than 200 mumol/L were randomized at the time of percutaneous transhepatic Cholangiography to undergo immediate or delayed surgery. The patients who had preoperative percutaneous transhepatic biliary drainage (PTBD) for 13.8 +/- 5.8 days had fewer surgical complications than did patients who underwent immediate surgery (p less than 0.02), although when the complications of PTBD were included this advantage was diminished. Immediate surgery caused greater deterioration of renal function as measured by plasma urea, plasma B 2-microglobulin, phosphate clearance, uric acid clearance, and maximal concentrating ability than occurred after PTBD or delayed surgery. The improvement in phosphate clearance that followed PTBD was sustained through delayed surgical treatment, indicating better tubular function in these patients. This article supports the concept that preoperative PTBD will reduce surgical morbidity and will result in less renal impairment than will immediate surgery. However, the morbidity rates of the PTBD procedure will preclude its wide use.

Factors affecting lower calyceal stone clearance after Extracorporeal ...

African Journals Online (AJOL)

Objective: Extracorporeal shock wave lithotripsy (ESWL) is one of the most commonly used procedures to remove renal calculi from the lower calyces. The aim of this work is to study the impact of radiological, anatomical and demographic factors on stone clearance after ESWL of lower calyceal calculi. Patients and ...

Evaluation of total renal function from 99mTc-MAG3 scintigraphy in children

International Nuclear Information System (INIS)

Andersson, L.G.; Bratteby, L.E.; Takalo, R.; Svensson, L.

2002-01-01

Aim: The aim of the present study was to evaluate the usefulness of dynamic scintigraphy in the assessment of total renal function in children. The Patlak slope of 99m Tc-MAG3 renography curves were compared to the plasma clearance values of 51Cr-EDTA. Material and methods: The study sample consisted of 53 boys and 33 girls with various nephrologic disorders, referred for routine clinical reasons. The median age of the subjects was 5.1 years (range 0.3 - 14.1 years). Imaging procedure. In supine position, the patient received a bolus injection of 1 MBq/kg, (minimum 10 MBq) 99m Tc-MAG3 and a posterior dynamic gamma camera registration was performed for 21 min using 1 frame per second during the first minute and thereafter 10 seconds frames. Data analysis. Time-activity curves were generated from manually drawn heart and renal regions of interest. The MAG3 uptake was calculated from the Patlak-Rutland plot of each kidney by linear curve fitting until the beginning of the excretory phase. A sum of the slope values was used as a measure of total renal MAG3 uptake. Cr-EDTA clearance. Glomerular filtration rate (GFR) was measured from the plasma clearance of 51 Cr-EDTA using single injection, multiple-sample technique. After intravenous injection of 51 Cr-EDTA (74 kBq/kg for children up to 7 years, 37 kBq/kg for children older than 7 years), blood samples were drawn at 5, 10, 15, 45, 60, 120 and 180 min for radioactivity measurement. The GFR was calculated according to Broechner-Mortensen and expressed in ml/min. Results: The absolute 51 Cr-EDTA clearance varied from 9 to 143 ml/min. There was a close linear relationship between 51 Cr-EDTA clearance and MAG3 uptake (Fig). The correlation coefficient was 0.90 and the regression equation (y=43.5 x + 664). Conclusions: In the present study, there was a good correlation between plasma clearance of 51 Cr-EDTA and the sum of the Patlak slopes. The regression equation can be utilised to transform the 99m Tc-MAG3 uptake to an

Assessment of split renal function with sup(99m)Tc-aprotinin

Energy Technology Data Exchange (ETDEWEB)

Aprile, C.; Saponaro, R.; Villa, G.; Carena, M.; Lunghi, F.; Salvadeo, A.; Solerte, S.B.

1986-05-01

The aim of this work is to correlate the net kidney uptake of sup(99m)Tc-aprotinin (TcA) in 103 subjects with separate effective renal plasma flow (ERPF) and some blood chemistry parameters at 90, 180, and 360 min postinjection both in the normal and diseased kidney. Correlations found with separate ERPFs are highly significant at any time. However, although the slope of the regression line is steeper at 180 min, r tends to deteriorate slightly with time postinjection and a higher intercept of the y axis; this pattern is more pronounced if diseased kidneys are considered separately. The following are probably related to the renal handling of TcA: (1) Early scans better reflect blood flow to the kidney, while later scans are more related to the metabolism/-excretion tubular mechanisms; (2) correlations found with urea, creatinine, urea clearance, and creatinine clearance are highly significant at any time; (3) in 20 additional patients with diseased kidneys, renal uptake measurements done 360 min postinjection first with TcA and then with MSA showed better correlations with ERPF employing TcA. Our results indicate that TcA is a feasible indicator of split renal function even at 90 min postinjections when a scan is easily carried out on an outpatient basis.

Association of clearance of middle- and large-molecular-weight substance with arterial stiffness and left ventricular mass in children receiving renal replacement therapy.

Science.gov (United States)

Özdemir, Kadriye; Yilmaz, Ebru; Dincel, Nida; Bozabali, Sibel; Apaydin, Sukriye; Gun, Zubeyr H; Sozeri, Betul; Mir, Sevgi

2017-12-01

The prominent cause of mortality in children receiving dialysis treatment is cardiovascular diseases. Risk factors related to chronic renal disease, are effective in the development of cardiovascular diseases. The aim of study was to investigate cardiovascular system (CVS) involvement for functional and structural alterations in children receiving dialysis, and display any association between cardiovascular morbidity and uremic toxins. 20 dialysis patients and 20 healthy controls were included to the study. Clearance of small, middle and large molecular-weight uremic toxins was evaluated in blood samples collected 30 minutes before (D0) and 2 hour after dialysis (D2), and change value was calculated as D0-D2/D0. Cardiovascular involvement was determined by comparing arterial stiffness, carotid intima-media thickness (CIMT) and Left Ventricular Mass Index (LVMI) with the control group. Four patients receiving hemodialysis and two patients in continuous ambulatory peritoneal dialysis (CAPD) group who have significant differences in all functional and structural parameters were detected. Four dialysis patients with detected cardiovascular disease have distinctively lower beta-2 microglobulin and homocysteine clearances compared to the patients with no CVS involvement. The clearance of middle and large molecular-weight substances should be closely monitored in children receiving dialysis.

Technetium-99m DTPA renal flow studies in Goldblatt hypertension

International Nuclear Information System (INIS)

Nally, J.V.; Clarke, H.S.; Windham, J.P.; Grecos, G.P.; Gross, M.L.; Potvin, W.J.

1985-01-01

Computer-assisted dynamic renal studies were performed on a group of 14 mongrel dogs before and after the induction of unilateral renal artery stenosis. Ninety-second technetium-99m diethylenetriaminepentaacetic acid ([/sup 99m/Tc]DTPA), 15-min [/sup 99m/Tc]DTPA, and 30-min iodine-131 orthoiodohippurate ([ 131 I]hippuran) time-activity curves were analyzed and correlated with reduction of renal blood flow as measured by electromagnetic flow probe and PAH clearance techniques. For blood flow reductions greater than 33%, the [/sup 99m/Tc]DTPA studies were judged diagnostic of unilateral renal artery stenosis in all cases, whereas the [ 131 I]hippuran time-activity curves were indicative of stenosis in only six of ten studies. Thus, in this model we find the computer-assisted 90-sec [/sup 99m/Tc]DTPA renal flow study to be superior to conventional [ 131 I]hippuran renography in the diagnosis of moderate-to-serve unilateral renal artery stenosis

Assessment of glomerular filtration rate and effective renal plasma flow in cystic fibrosis

International Nuclear Information System (INIS)

Spino, M.; Chai, R.P.; Isles, A.F.; Balfe, J.W.; Brown, R.G.; Thiessen, J.J.; MacLeod, S.M.

1985-01-01

A study was conducted to examine renal function in 10 healthy control subjects and eight patients with cystic fibrosis in stable condition. Sequential bolus injections of /sup 99m/Tc-DTPA and 125 I-OIH were administered to assess glomerular filtration rate and effective renal plasma flow, respectively. Blood was subsequently collected for 3 hours, and urine for 24 hours. Renal clearances of both radioisotope markers were virtually identical in patients and controls. Inasmuch as neither glomerular filtration rate nor effective renal plasma flow was enhanced in patients with cystic fibrosis, increased clearance of drugs in these patients is unlikely to be the result of enhanced glomerular filtration or tubular secretion

Population pharmacokinetics of teicoplanin in hospitalized elderly patients using cystatin C as an indicator of renal function.

Science.gov (United States)

Kasai, Hidefumi; Tsuji, Yasuhiro; Hiraki, Yoichi; Tsuruyama, Moeko; To, Hideto; Yamamoto, Yoshihiro

2018-04-01

Serum cystatin C (CysC) has recently been proposed as an alternative marker to serum creatinine (SCR) for estimating renal clearance. In the present study, we performed a population pharmacokinetic analysis of teicoplanin (TEIC), which is mainly eliminated through the kidneys, using CysC as a predictor for renal clearance. Thirty-six patients with MRSA infections who were administrated to the National Hospital Organization Beppu Medical Center between January 2012 and December 2013 were enrolled and gave 123 sets of blood TEIC concentration data. Renal clearance was estimated by the Hoek equation using CysC, by creatinine clearance predicted by the Cockcroft-Gault equation using SCR, or directly by CysC. One compartment open model with inter-individual variabilities for renal clearance and the volume of distribution as well as an additional residual error model was used to estimate population pharmacokinetic parameters for TEIC. The model with the best predictability was that with CysC as a predictor for renal clearance; it showed better significance than the models using estimated the glomerular filtration rate by the Hoek equation or CLcr. The final model was as follows: CL (L/hr) = 0.510 × (CysC/1.4) -0.68  × Total body weight/60 0.81 , omega (CL) = 19.8% CV, VC (L) = 78.1, omega (V) = 42.7% CV. The present results show the usefulness of CysC to more accurately predict the pharmacokinetics of drugs mainly eliminated through the kidneys, such as TEIC. However, since the sample size in this study was relatively small, further investigations on renal clearance predictability using CysC are needed. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Radioisotopic investigation of renal arterial hypertension using 99m Tc-DTPA

International Nuclear Information System (INIS)

Champailler, A.; Defour-Decousus, M.; Houzard, C.; Healy, J.C.; Gonthier, R.; Juge, J.; Berthoux, F.C.

1984-01-01

To evaluate the clinical validity of renal investigation using 99m Tc-DTPA, 60 hypertensive patients divided into four groups according to diagnosis were studied: 1) renovascular hypertension (22 patients); 2) chronic pyelo-nephritis (11 patients); 3) renal hypoplasia (12 patients); 4) hypertension due to bilateral parenchymatous (15 patients). A good correlation was found between clearance of DTPA and creatinine clearance/1.73 m 2 body surface (n = 51, r = 0.68, p 2 BS [fr

Recent activities on clearance in IAEA and clearance automatic laser inspection system (CLALIS)

International Nuclear Information System (INIS)

Hattori, Takatoshi; Sasaki, Michiya

2005-01-01

Exemption levels for bulk amounts of materials have been described in RS-G-1.7 published as a safety guide in IAEA on August 2004. In Japan, the Nuclear Safety Commission adopted the RS-G-1.7 values as Japanese clearance levels after the careful review of dose assessment results. After completing revises of regulatory laws in relation to clearance level, solid wastes from decommissioning and operating nuclear power plants will be targets of clearance inspection. In CRIEPI, Clearance Automatic Laser Inspection System (CLALIS) has been developed, which can give high reliability and objectivity to the measurement data. The CLALIS is a new monitoring system coupling with 3D laser shape measurement, Monte-Carlo calculation and gamma measurement techniques, which can keep a high accuracy in the measurement data using an automatic correction technique for self-shielding effects of metal waste itself and is expected to apply as a practical use in actual clearance inspections. (author)

Study on clearance system

International Nuclear Information System (INIS)

Onishi, Yuko; Miura, Hiroshi; Kawasaki, Satoru

2011-01-01

The clearance system is a legal system to release 'the radioactive waste not requiring treatment as radioactive waste' from the regulatory control. JNES supports NISA on approval and confirmation of clearance measurement and judgment developed by the operator. The objective of this study is to establish technical base of the validation method of the clearance measurement for various objects. In reactor facilities, the bulk measurement technique or the statistical sampling measurement technique may be applied to large scale objects or concrete walls. In this study, the criteria of those techniques were examined. In uranium processing facilities, it is important to confirm surface state of the object in case of detecting alpha rays. The result of the examination about the influence of the surface rust in the uranium clearance measurement by the alpha ray measurement showed that the pollution was distributed in rust layer uniformly. This result will be reflected to the revision of the Ministerial Ordinance on Clearance in 2011FY. To develop a manual for unexpected incidents, the response procedure for an unexpected incident was prepared, including a response system. (author)

Study on clearance system

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-15

The clearance system is a legal system to release 'the radioactive waste not requiring treatment as radioactive waste' from the regulatory control. JNES supports Nuclear Regulatory Agency on approval and confirmation of clearance measurement and judgment developed by the operator. The objective of this study is to establish technical base of the validation method of the clearance measurement for various objects. In uranium processing facilities, simulation sources emitting alpha-rays is used in a validity confirmation examination of the measuring equipment. In this study, these sources were examined by measuring alpha and beta spectra to evaluate the applicability and problem of these sources. In addition, the measuring method detecting gamma-rays was examined. This method can be applied to complicated objects. As a part to develop a manual for unexpected incidents in clearance system, a quick method for measurement of Strontium 90 was examined. In addition, the measuring methods for the judgment of the influence of fallout and for NR (Non-Radioactive) confirmation were examined. (author)

The clearance concept with special reference to determination of glomerular filtration rate in patients with fluid retention

DEFF Research Database (Denmark)

Henriksen, Ulrik L; Henriksen, Jens H

2014-01-01

In subjects without fluid retention, the total plasma clearance of a renal filtration indicator (inulin, (99m) Tc-DTPA, (51) Cr-EDTA) is close to the urinary plasma clearance. Conversely, in patients with fluid retention (oedema, pleural effusions, ascites), there is a substantial discrepancy...

Proficiency testing criteria for clearance level in solid waste gamma measurement in Taiwan

International Nuclear Information System (INIS)

Chen, Chun-Liang; Wang, Jeng-Jong; Chiu, Huang-Sheng

2013-01-01

To guarantee the measurement quality for clearance level in solid waste material, the Institute of Nuclear Energy Research (INER) established the criteria for proficiency testing of clearance level measurement. INER and the Taiwan Accreditation Foundation (TAF) organized the Technique Committee Meeting twice to discuss these criteria in 2011. The participating laboratories must completely conform to the ISO/IEC 17025, and they also must meet the requirements of the criteria. According to the criteria, the participating laboratories analyzed the minimum detectable amount (MDA) and that should be less than 20% of the clearance level (AMDA) given in the Atomic Energy Council's (AEC) “Regulations on Clearance Level for Radioactive Waste Management”. The testing results should conform to the deviation and traceability requirements. - Highlights: • The participating laboratories must completely conform to the ISO/IEC 17025 • The proficiency testing items were basically in two categories, box and barrel types • Analyzed the MDA and that should be less than 20% of the release level given in the AEC. • The are three limitations: MDA< AMDA, -0.25< Bi<+0.5, and En≤1.0 and uncertainty<20%

Creatinine Clearance and Estimated Glomerular Filtration Rate – When are they Interchangeable

OpenAIRE

Šimetić, Lucija; Zibar, Lada; Drmić, Sandra; Begić, Ivana; Šerić, Vatroslav

2015-01-01

Study goal was to examine which of glomerular rate equations is most suitable for prediction of creatinine clearance. Using a retrospective review of data from 500 hospital patients we calculated glomerular filtration rate according to Cockcroft-Gault equation (C-G), Modification of Diet in Renal Disease Study equation (MDRD) and Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). We determined if results of these equations were compatible with creatinine clearance, and does...

[Why? How? What for? We must measure the glomerular filtration].

Science.gov (United States)

Treviño-Becerra, Alejandro

2010-01-01

The measurement of the glomerular filtration shows the degree of the functional qualities and the proficiency of the renal system. Despite new technologies, at present the best accepted technique for measuring the glomerular filtration in most countries is the clearance of creatinine in 24 hour urine. The clearance of creatinine has the advantage that it is confident, easy to reproduce, without technical limitations and low cost.

Sinvastatina e lesão renal aguda isquêmica em ratos Simvastatina y lesión renal aguda isquémica en ratas Simvastatin and acute ischemic renal injury in rats

Directory of Open Access Journals (Sweden)

Claudia Akemi Shibuya Teshima

2012-01-01

Full Text Available OBJETIVOS: O estudo visou verificar a ação renoprotetora da sinvastatina em modelo animal de isquemia/reperfusão por 30 minutos. MÉTODOS: A isquemia foi obtida por meio do clampeamento dos pedículos renais bilaterais por 30 minutos, seguida de reperfusão. Ratos Wistar, machos foram usados pesando entre 250-300g, distribuídos nos seguintes grupos: SHAM (controle, sem clampeamento renal; Isquemia (isquemia renal por 30 minutos; Isquemia+Estatina (sinvastatina 0,5 mg/kg, via oral durante três dias. A função renal (clearance de creatinina, método de Jaffé, a osmolalidade urinária, os peróxidos urinários foram avaliados. RESULTADOS: Os resultados mostraram que a estatina melhorou a função renal, a osmolalidade urinária e reduziu a excreção de PU. CONCLUSÃO: Em síntese, o estudo confirmou o efeito renoprotetor da estatina, com ação antioxidante de proteção renal.OBJETIVOS: El estudio tuvo como objetivo verificar la acción renoprotectora de la simvastatina en modelo animal de isquemia/reperfusión por 30 minutos. MÉTODOS: La isquemia se obtuvo por medio del pinzamiento de los pedículos renales bilaterales por 30 minutos, seguida de la reperfusión. Fueron usadas ratas Wistar, machos que pesaban entre 250-300g, distribuidos en los siguientes grupos: SHAM (control, sin pinzamiento renal; Isquemia (isquemia renal por 30 minutos; Isquemia+Estatina (simvastatina 0,5 mg/kg, via oral durante tres días. Fueron evaluadas la función renal (clearance de creatinina, método de Jaffé, la osmolaridad urinaria y los peróxidos urinarios. RESULTADOS: Los resultados mostraron que la estatina mejoró la función renal, la osmolaridad urinaria y redujo la excreción de PU. CONCLUSIÓN: En síntesis, el estudio confirmó el efecto renoprotector de la estatina, con acción antioxidante de protección renal.OBJECTIVES: The study aimed to verify the protective renal action of simvastatin in an animal model of ischemia / reperfusion for 30

Pharmacokinetics of sugammadex in subjects with moderate and severe renal impairment
.

Science.gov (United States)

Min, K Chris; Lasseter, Kenneth C; Marbury, Thomas C; Wrishko, Rebecca E; Hanley, William D; Wolford, Dennis G; Udo de Haes, Joanna; Reitmann, Christina; Gutstein, David E

2017-09-01

Sugammadex rapidly reverses moderate and deep rocuronium- or vecuronium-induced neuromuscular blockade at doses of 4 mg/kg and 2 mg/kg, respectively. Sugammadex is renally eliminated. This study evaluated the pharmacokinetics of sugammadex in subjects with renal impairment versus those with normal renal function. This open-label, two-part, phase 1 study included adults with moderate (creatinine clearance (CLcr) 30 - cr cr ≥ 80 mL/min). A single intravenous (IV) bolus injection of sugammadex 4 mg/kg was administered into a peripheral vein over 10 seconds directly by straight needle in part 1 (n = 24; 8/group), and via an IV catheter followed by a saline flush in part 2 (n = 18; 6/group). Plasma concentrations of sugammadex were collected after drug administration. Due to dosing issues in part 1, pharmacokinetic parameters were determined for part 2 only. Safety was assessed throughout the study. Pharmacokinetic data were obtained from 18 subjects. Mean sugammadex exposure (AUC0-∞) in subjects with moderate and severe renal impairment was 2.42- and 5.42-times, respectively, that of healthy controls. Clearance decreased and apparent terminal half-life was prolonged with increasing renal dysfunction. Similar Cmax values were observed in subjects with renal impairment and healthy controls. There were no serious adverse events. Sugammadex exposure is increased in subjects with moderate and severe renal insufficiency due to progressively decreased clearance as a function of worsening renal function. Sugammadex 4 mg/kg was well tolerated in subjects with renal impairment, with a safety profile similar to that of healthy subjects. These results indicate that dose adjustment of sugammadex is not required in patients with moderate renal impairment; however, current safety experience is insufficient to support the use of sugammadex in patients with CLcr < 30 mL/min.
.

Non-steroidal anti-inflammatory drugs and renal response to exercise

DEFF Research Database (Denmark)

Olsen, Niels Vidiendal; Jensen, N G; Hansen, J M

1999-01-01

baseline values or exercise-induced decreases in renal plasma flow or glomerular filtration rate. Indomethacin, but not nabumetone, decreased sodium excretion, urine flow rate and free water clearance. The renal response to exercise, however, remained unchanged. In contrast with nabumatone, indomethacin...

Marcadores práticos de função renal em pacientes com cistinose

Directory of Open Access Journals (Sweden)

Luciana Pache de Faria Guimaraes

2012-09-01

Full Text Available INTRODUÇÃO: Cistinose é uma doença sistêmica, autossômica recessiva, que leva à insuficiência renal crônica na infância, a não ser que o tratamento com cisteamina seja iniciado precocemente. Mesmo nestas condições, os pacientes evoluem para doença renal crônica terminal por volta da segunda década da vida. Portanto, a avaliação da função renal é essencial neste grupo de pacientes. OBJETIVO: Avaliar e correlacionar a cistatina C, creatinina sérica e o clearance de creatinina pela Fórmula de Schwartz em pacientes com cistinose, com diferentes graus de função renal. MÉTODOS: Foram incluídos pacientes com menos de 18 anos de idade, com diferentes níveis de função renal, de acordo com o KDOQI em estágios 1 a 4. Nenhum dos pacientes estava em terapia de substituição renal. Foram medidos os seguintes parâmetros: cistatina C, creatinina sérica e o clearance de creatinina pela fórmula de Schwartz. RESULTADOS: Foram analisadas 103 amostras de sangue de 26 pacientes. Foi detectada correlação significativa entre creatinina sérica e cistatina C (r = 0,81, p < 0,0001, cistatina C e o clearance de creatinina pela fórmula de Schwartz (r = -0,84, p < 0,0001 e creatinina sérica e clearance de creatinina (r = -0,97, p < 0,0001. CONCLUSÕES: A medida da cistatina não mostrou nenhuma vantagem sobre a creatinina sérica e o clearance de creatinina pela fórmula de Schwartz em pacientes com cistinose para avaliar o ritmo de filtração glomerular. Este é o primeiro relato sobre o valor da creatinina sérica, do clearance de creatinina pela fórmula de Schwartz e da cistatina C em pacientes com cistinose.

Cine-CT measurement of cortical renal blood flow

International Nuclear Information System (INIS)

Jaschke, W.R.; Gould, R.G.; Cogan, M.G.; Sievers, R.; Lipton, M.J.

1987-01-01

A modified indicator-dilution technique using radiographic contrast material and a cine-CT scanner was used to measure blood flow in the renal cortex of dogs. To validate this technique, CT measurements were correlated with simultaneous measurements of flow determined by radioactive microspheres. Measurements were taken during euvolemic conditions and after hemorrhage. Thirty-nine measurements were compared, covering a flow range from 1 to 7 ml min-1 g-1, and a good correlation was found between the cine-CT and microsphere results (r = 0.93; p less than 0.001). Additionally, cine-CT measurements were made of the mean transit time (MTT) of contrast material through the renal cortex, and the reciprocal of these MTT values was also well correlated to microsphere determined flow (r = 0.94; p less than 0.001). Thus, cine-CT appears to be a promising new technique for measuring renal blood flow

A role for the organic anion transporter OAT3 in renal creatinine secretion in mice

Science.gov (United States)

Eraly, Satish A.; Rao, Satish Ramachandra; Gerasimova, Maria; Rose, Michael; Nagle, Megha; Anzai, Naohiko; Smith, Travis; Sharma, Kumar; Nigam, Sanjay K.; Rieg, Timo

2012-01-01

Tubular secretion of the organic cation, creatinine, limits its value as a marker of glomerular filtration rate (GFR) but the molecular determinants of this pathway are unclear. The organic anion transporters, OAT1 and OAT3, are expressed on the basolateral membrane of the proximal tubule and transport organic anions but also neutral compounds and cations. Here, we demonstrate specific uptake of creatinine into mouse mOat1- and mOat3-microinjected Xenopus laevis oocytes at a concentration of 10 μM (i.e., similar to physiological plasma levels), which was inhibited by both probenecid and cimetidine, prototypical competitive inhibitors of organic anion and cation transporters, respectively. Renal creatinine clearance was consistently greater than inulin clearance (as a measure of GFR) in wild-type (WT) mice but not in mice lacking OAT1 (Oat1−/−) and OAT3 (Oat3−/−). WT mice presented renal creatinine net secretion (0.23 ± 0.03 μg/min) which represented 45 ± 6% of total renal creatinine excretion. Mean values for renal creatinine net secretion and renal creatinine secretion fraction were not different from zero in Oat1−/− (−0.03 ± 0.10 μg/min; −3 ± 18%) and Oat3−/− (0.01 ± 0.06 μg/min; −6 ± 19%), with greater variability in Oat1−/−. Expression of OAT3 protein in the renal membranes of Oat1−/− mice was reduced to ∼6% of WT levels, and that of OAT1 in Oat3−/− mice to ∼60%, possibly as a consequence of the genes for Oat1 and Oat3 having adjacent chromosomal locations. Plasma creatinine concentrations of Oat3−/− were elevated in clearance studies under anesthesia but not following brief isoflurane anesthesia, indicating that the former condition enhanced the quantitative contribution of OAT3 for renal creatinine secretion. The results are consistent with a contribution of OAT3 and possibly OAT1 to renal creatinine secretion in mice. PMID:22338083

Renal clearance of an ionic high-osmolar and a nonionic low-osmolar contrast medium

International Nuclear Information System (INIS)

Thomsen, H.S.; Vestergaard, A.; Nielsen, S.L.; Fogh-Andersen, N.; Golman, K.; Dorph, S.

1991-01-01

One hundred patients with normal serum creatinine concentration underwent intravenous urography with either an ionic high-osmolar (diatrizoate) or a nonionic low-osmolar (iopamidol) contrast medium after randomization. Before injection of the contrast medium, a blood sample was drawn for determinating serum creatinine concentration, and a urine sample for measurement of urine osmolality. Using x-ray fluorescence, the plasma concentration of iodine (contrast medium) was determined on blood samples drawn approximately 3 and 4 hours after injection of the contrast medium. The glomerular filtration rate was calculated by two different formulas: one requiring only a single sample and one requiring at least two samples (standard). There were poor correlations between the standard contrast medium clearance and the serum creatinine concentration, the estimated creatinine clearance (calculated from a nomogram), as well as the urine osmolality. The 3-hour and the 4-hour single-sample values correlated well with the two-sample values for both contrast media. In patients with normal serum creatinine, the glomerular filtration rate determined by measuring the contrast medium concentration in a single plasma sample obtained at 3 hours, is almost identical to the value determined from two samples. Consequently, two samples are unnecessary

Efficacy of the lithotripsy in treating lower pole renal stones.

Science.gov (United States)

Cui, Helen; Thomee, Eeke; Noble, Jeremy G; Reynard, John M; Turney, Benjamin W

2013-06-01

Use of extracorporeal lithotripsy is declining in North America and many European countries despite international guidelines advocating it as a first-line therapy. Traditionally, lithotripsy is thought to have poor efficacy at treating lower pole renal stones. We evaluated the success rates of lithotripsy for lower pole renal stones in our unit. 50 patients with lower pole kidney stones ≤15 mm treated between 3/5/11 and 19/4/12 were included in the study. Patients received lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter according to a standard protocol. Clinical success was defined as stone-free status or asymptomatic clinically insignificant residual fragments (CIRFs) ≤3 mm at radiological follow-up. The mean stone size was 7.8 mm. The majority of stones (66 %) were between 5 and 10 mm. 28 % of stones were between 10 and 15 mm. For solitary lower pole stones complete stone clearance was achieved in 63 %. Total stone clearance including those with CIRFs was achieved in 81 % of patients. As expected, for those with multiple lower pole stones the success rates were lower: complete clearance was observed in 39 % and combined clearance including those with CIRFs was 56 %. Overall, complete stone clearance was observed in 54 % of patients and clearance with CIRFs was achieved in 72 % of patients. Success rate could not be attributed to age, stone size or gender. Our outcome data for the treatment of lower pole renal stones (≤15 mm) compare favourably with the literature. With this level of stone clearance, a non-invasive, outpatient-based treatment like lithotripsy should remain the first-line treatment option for lower pole stones. Ureteroscopy must prove that it is significantly better either in terms of clinical outcome or patient satisfaction to justify replacing lithotripsy.

Increased Renal Clearance of Rocuronium Compensates for Chronic Loss of Bile Excretion, via upregulation of Oatp2.

Science.gov (United States)

Wang, Long; Zhou, Mai-Tao; Chen, Cai-Yang; Yin, Wen; Wen, Da-Xiang; Cheung, Chi-Wai; Yang, Li-Qun; Yu, Wei-Feng

2017-01-13

Requirement for rocuronium upon surgery changes only minimally in patients with end-stage liver diseases. Our study consisted of both human and rat studies to explore the reason. The reduction rate of rocuronium infusion required to maintain neuromuscular blockade during the anhepatic phase (relative to paleohepatic phase) was examined in 16 children with congenital biliary atresia receiving orthotopic liver transplantation. Pharmacodynamics and pharmacokinetics of rocuronium were studied based on BDL rats. The role of increased Oatp2 and decrease Oatp1 expressions in renal compensation were explored. The reduction of rocuronium requirements significantly decreased in obstructively jaundiced children (24 ± 9 vs. 39 ± 11%). TOF50 in BDL rats was increased by functional removal of the kidneys but not the liver, and the percentage of rocuronium excretion through urine increased (20.3 ± 6.9 vs. 8.6 ± 1.8%), while that decreased through bile in 28d-BDL compared with control group. However, this enhanced renal secretion for rocuronium was eliminated by Oatp2 knock-down, rather than Oatp1 overexpression (28-d BDL vs. Oatp1-ShRNA or Oatp2-ShRNA, 20.3 ± 6.9 vs. 17.0 ± 6.6 or 9.3 ± 3.2%). Upon chronic/sub-chronic loss of bile excretion, rocuronium clearance via the kidneys is enhanced, by Oatp2 up-regulation.

Assessment of split renal function with sup(99m)Tc-aprotinin

International Nuclear Information System (INIS)

Aprile, C.; Saponaro, R.; Villa, G.; Solerte, S.B.

1986-01-01

The aim of this work is to correlate the net kidney uptake of sup(99m)Tc-aprotinin (TcA) in 103 subjects with separate effective renal plasma flow (ERPF) and some blood chemistry parameters at 90, 180, and 360 min postinjection both in the normal and diseased kidney. Correlations found with separate ERPFs are highly significant at any time (P<0.001). However, although the slope of the regression line is steeper at 180 min, r tends to deteriorate slightly with time postinjection and a higher intercept of the y axis; this pattern is more pronounced if diseased kidneys are considered separately. The following are probably related to the renal handling of TcA: (1) Early scans better reflect blood flow to the kidney, while later scans are more related to the metabolism/-excretion tubular mechanisms; (2) correlations found with urea, creatinine, urea clearance, and creatinine clearance are highly significant at any time; (3) in 20 additional patients with diseased kidneys, renal uptake measurements done 360 min postinjection first with TcA and then with MSA showed better correlations with ERPF employing TcA. Our results indicate that TcA is a feasible indicator of split renal function even at 90 min postinjections when a scan is easily carried out on an outpatient basis. (orig.)

Euthyroid sick syndrome in patients with acute renal failure

International Nuclear Information System (INIS)

Ilic Slobodan; Vlajkovic Marina; Rajic Milena; Bogicevic Momcilo

2004-01-01

Objectives: The purpose of this study was to evaluate serum thyroid hormone profile in acute renal failure (ARF) patients according to the initial 131I-OIH clearance value as a predictor of ARF outcome. Patients and methods: Radioimmuno-assays of T4, T3, FT4, FT3, rT3 and TSH were performed in 32 ARF patients within 7 days and 6 months after ARF onset. The patients were divided into three groups according to the kidney function recovery potential measured by 131I-OIH clearance as follows: Group I: high probability for kidney recovery (131I-OIH clearance >250 ml/min), Group II: intermediate probability for kidney recovery (131I-OIH clearance 151-250 ml/min) and Group III: low probability for kidney recovery (131I-OIH clearance <150 ml/min). The results were compared with those obtained in 20 healthy patients. Results: Total thyroid hormone and TSH values are displayed in the table, Values of total T4 and TSH were slightly declined in the Group I but without reaching the statistical significance, while total T3 value was significantly decreased seven days after ARF onset. In the groups with intermediate and low probability for kidney recovery both T3 and T4 values were significantly dropped, being most prominent in the III group. After six months, the most severe fall of thyroid hormone levels without reaching the normalization was found only in the Group III while in the Group I and II normalization of total thyroid hormone levels was achieved. At the end of the observation period ARF patients with low probability for kidney recovery were found significantly lower values of TSH. Conclusion: Acute renal failure affects thyroid function leading to euthyroid sick syndrome characterized by declined serum T3 and T4 without TSH elevation. Thyroid hormone a disturbance is in accordance with the impairment of renal function being the most pronounced in patient with low probability for kidney recovery. This pattern of altered thyroid hormone levels could be a result of

Projecting ADME Behavior and Drug-Drug Interactions in Early Discovery and Development: Application of the Extended Clearance Classification System.

Science.gov (United States)

El-Kattan, Ayman F; Varma, Manthena V; Steyn, Stefan J; Scott, Dennis O; Maurer, Tristan S; Bergman, Arthur

2016-12-01

To assess the utility of Extended Clearance Classification System (ECCS) in understanding absorption, distribution, metabolism, and elimination (ADME) attributes and enabling victim drug-drug interaction (DDI) predictions. A database of 368 drugs with relevant ADME parameters, main metabolizing enzymes, uptake transporters, efflux transporters, and highest change in exposure (%AUC) in presence of inhibitors was developed using published literature. Drugs were characterized according to ECCS using ionization, molecular weight and estimated permeability. Analyses suggested that ECCS class 1A drugs are well absorbed and systemic clearance is determined by metabolism mediated by CYP2C, esterases, and UGTs. For class 1B drugs, oral absorption is high and the predominant clearance mechanism is hepatic uptake mediated by OATP transporters. High permeability neutral/basic drugs (class 2) showed high oral absorption, with metabolism mediated generally by CYP3A, CYP2D6 and UGTs as the predominant clearance mechanism. Class 3A/4 drugs showed moderate absorption with dominant renal clearance involving OAT/OCT2 transporters. Class 3B drugs showed low to moderate absorption with hepatic uptake (OATPs) and/or renal clearance as primary clearance mechanisms. The highest DDI risk is typically seen with class 2/1B/3B compounds manifested by inhibition of either CYP metabolism or active hepatic uptake. Class 2 showed a wider range in AUC change likely due to a variety of enzymes involved. DDI risk for class 3A/4 is small and associated with inhibition of renal transporters. ECCS provides a framework to project ADME profiles and further enables prediction of victim DDI liabilities in drug discovery and development.

Aspects of osseous, peritoneal and renal handling of bisphosphonate during peritoneal dialysis: a methodological study

DEFF Research Database (Denmark)

Joffe, P; Henriksen, Jens Henrik

1996-01-01

to continuous ambulatory peritoneal dialysis (CAPD). The aims were: to assess the kinetics of 99m-technetium MBP (99mTc-MBP) in CAPD, and to evaluate the correctness of the assumption that the peritoneal and renal clearances of 99mTc-MBP equal the total plasma clearance of 51-chromium ethylenediamine tetra......Tc-MBP equal the clearances of 51Cr-EDTA is correct from a clinical point of view. We found that the uptake of the tracers in soft tissue and the renal handling of 51Cr-EDTA and 99mTc-MBP are also similar. The differences between the clearance values for 51Cr-EDTA and 99mTc-MBP may be explained...

Outcome and renal function following salvage surgery for bilateral ...

African Journals Online (AJOL)

Objective: The aim of this study was to determine the surgical outcomes and renal function following salvage surgery for bilateral Wilms tumor (BWT). Summary background data The challenge for the surgeon treating BWT lies in striking a fine balance between renal preservation and oncological clearance. Methods: This is ...

Measurement of Regional and Global Pulmonary Clearance of 99mTc-DTPA (Demethylamitriptylene-Acetate): An Index of Alveolar Epithelial Permeability

International Nuclear Information System (INIS)

Vaskova, Olivija

1996-01-01

The main purpose of this study has been introduction of a new method for alveoli-capillary permeability evaluation. Many reports pointed out to the altered transit of soluble particles through this barrier. From pathophysiological aspect the main interest is the elucidation of permeability's alteration in different pulmonary pathology. We decided to use for lung epithelial permeability measurements 99m Tc-DTPA inhaled aerosols and sequential assessment of its lung clearance. The aerosols were obtained using oxygen flow nebulizers with aerosols' generators Ultra Vent (Malinkrodt) and Venticis II (CIS bio international) that enabled as to get submicron particles. Oxygen flow between 9 and 11 liters per minute was used. Optimum images were obtained with 1480 MBq of inhaled aerosols at least 2 to 3 minutes. DTPA that was used for aerosols labeling had been produced in our Department and the results were compared with DTPA provided by CIS bio international. High correlation between both agents was proven. During the whole study ex tamper prepared radiopharmaceuticals were used and quality control was done using paper chromatography method. Acquisition was done in sitting position with gamma camera interfaced to a ADAC and Scintiview. The measurements lasted for 20 minutes. Data were stored on 64x64 matrices. Regions of interest over both lungs were drown and each one was divided in three segments: apical, medial, and basal. Using computer program curves of 99m Tc-DTPA lung clearance were derived. From the obtained time activity curves half-time of the global and the regional lung clearance was assessed. In the control group comprised of 32 healthy volunteers (non-smokers) we had got values, used after works as reference range. Our normal values for global clearance are: 68±5,5 min. for left whole lung, 68,1±6,5 min for right whole lung, and 49±7,7 min for apical, 66,9±8 min for middle, and 75,9±6,4 min basal regional lung clearance, and they are in keeping with the

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.

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.

Homocystein and carotid atherosclerosis in chronic renal failure.

Science.gov (United States)

Lubomirova, M; Tzoncheva, A; Petrova, J; Kiperova, B

2007-10-01

Since total homocysteine (Hcy) is markedly elevated in patients with chronic renal failure (CRF), it has been presented as potential factor contributing to the high risk of cardiovascular disease (CVD) in CRF. The aim of the study was to examine the significance of elevated Hcy and other cardiovascular risk factors for carotid atherosclerosis in patients with CRF. Fifty six patients 16-M, 40-F, average age 58+/-14.55, creatinine clearance 39.19+/-10.11 ml/min were examined. In addition, 20 control healthy subjects were examined. The association of Hcy levels and classic risk factors for atherosclerosis with common carotid intima-media thickness (IMT) was examined. B-mode ultrasound measurement of carotid IMT was performed in 56 hypertensive pts with CRF (glomerular filtration rate>20 ml/min and 0.05). Significant predictors for IMT were age (r=0.358, p<0.04), duration of hypertension (r=0.395, p=0.023), diabetes duration (r=0.343, p<0.02), as well as duration of CRF (r=0.324, p<0.006). There was a negative correlation between IMT and glomerular filtration rate assessed by creatinine clearance (r=-0.303, p<0.003). Renal function, described by creatinine clearance was the strongest determinant for Hcy levels (r=-0.332, p<0.008). Increased IMT was estimated in pts with CRF compared to healthy controls (0.74+/-0.10 vs 0.59+/-0.10, p<0.001). We found association between Hcy and carotid IMT ( r=0.344, p<0.015). No consistent association was found between IMT and other specific for CRF cardiovascular risk factors. The study suggests that patients with mild renal failure have increased IMT of the common carotid artery and that elevated plasma Hcy level in CRF is associated with carotid intima- media thickening.

Reversal deterioration of renal function accompanied with primary hypothyrodism.

Science.gov (United States)

Dragović, Tamara

2012-02-01

Hypothyroidism is often accompanied with decline of kidney function, or inability to maintain electrolyte balance. These changes are usually overlooked in everyday practice. Early recognition of this association eliminates unnecessary diagnostic procedures that postpone the adequate treatment. Two patients with elevated serum creatinine levels due to primary autoimmune hypothyroidism, with complete recovery of creatinine clearance after thyroid hormone substitution therapy are presented. The first patient was a young male whose laboratory tests suggested acute renal failure, and the delicate clinical presentation of reduced thyroid function. The second patient was an elderly woman with a history of a long-term signs and symptoms attributed to ageing, including the deterioration of renal function, with consequently delayed diagnosis of hypothyroidism. Serum thyrotropin and thyroxin levels measurement should be done in all cases of renal failure with undefined renal desease, even if the typical clinical presentation of hypothyroidism is absent. Thyroid hormone assays sholud also be performed in all patients with chronic kidney disease whose kidney function is rapidly worsening.

The pharmacokinetics of piroxicam in elderly persons with and without renal impairment.

Science.gov (United States)

Rudy, A C; Figueroa, N L; Hall, S D; Brater, D C

1994-01-01

1. Piroxicam pharmacokinetics were assessed in three groups of subjects: (1) young healthy volunteers, (2) healthy elderly subjects (mean +/- s.d. creatinine clearance 88 +/- 13 ml min-1), and (3) elderly patients with renal insufficiency (creatinine clearance 60 +/- 10 ml min-1) following the administration of piroxicam 20 mg as a single dose and after chronic dosing of 20 mg once daily for 4 weeks. 2. Piroxicam and 5'-hydroxypiroxicam concentrations were measured by h.p.l.c. in serum and urine samples collected for 96 h after the single dose and for 144 h after chronic dosing. Unbound concentrations of piroxicam were determined by ultrafiltration. 3. Elimination half-lives, steady state concentrations of piroxicam and 5'-hydroxypiroxicam, clearances of total and unbound piroxicam, volumes of distribution normalized for body weight, and urinary recovery of 5'-hydroxypiroxicam were not influenced by age or renal function. Volumes of distribution after the single dose were significantly lower in women compared with men (mean +/- s.d. 10.0 +/- 2.9 l vs 12.9 +/- 5.0 l; 95% confidence interval of the difference 0.1 to 5.6). 4. Percent unbound piroxicam values were 1.46 +/- 0.3% after the single dose and 1.45 +/- 0.2% at steady state. There were significant reductions in clearance and clearance of unbound piroxicam between single and chronic doses. The half-lives of 5'-hydroxypiroxicam (80.9 +/- 44 h) were significantly longer than those of piroxicam (54.9 +/- 26 h) after chronic dosing. PMID:8148211

Renal function changes associated with aging and ionizing radiation

International Nuclear Information System (INIS)

Miller, C.W.; Norrdin, R.W.; Sawyer, S.S.; Nealeigh, R.C.

1978-01-01

Renal function testing of irradiated and unirradiated beagles at CRHL has been carried out for the past 7 years using a simultaneous estimation of sodium sulfanilate and sodium iodohippurate 131 I clearance. Evidence has been cited that the beagle kidney is markedly sensitive to whole-body ionizing radiation delivered in the perinatal period. The objectives of this continuing study are to determine the nature of the progression of chronic renal disease, its possible association to hypertension, the impact of unilateral nephrectomy upon an already compromised renal parenchyma, and the age-related changes in renal function. Thus far, data seem to indicate the following conclusions: sulfanilate clearance appears to be a sensitive indicator of impending renal failure, exhibiting earlier and more obvious indicators than BUN (blood urea nitrogen) levels; hypertension does not appear to be a factor in radiation-induced renal failure in the adult dogs studied here, since the average arterial blood pressure was as high in normal control dogs as in irradiated dogs suffering from renal failure; unilateral nephrectomy affected unirradiated dogs less than irradiated animals with mild renal insufficiency. The BUN levels returned to prenephrectomy levels in 8 weeks in the unirradiated group, but required up to 1 year in the dogs with renal insufficiency; and an age related decrease inrenal function was observed in a group of unirradiated dogs studied from 0 to 2 through 13 years of age

Direct measurement of first-pass ileal clearance of a bile acid in humans

International Nuclear Information System (INIS)

Galatola, G.; Jazrawi, R.P.; Bridges, C.; Joseph, A.E.; Northfield, T.C.

1991-01-01

The purpose of this study was to develop and validate a method of directly measuring ileal bile acid absorption efficiency during a single enterohepatic cycle (first-pass ileal clearance). This has become feasible for the first time because of the availability of the synthetic gamma-labeled bile acid 75Selena-homocholic acid-taurine (75SeHCAT). Together with the corresponding natural bile acid cholic acid-taurine (labeled with 14C), SeHCAT was infused distal to an occluding balloon situated beyond the ampulla of Vater in six healthy subjects. Completion of a single enterohepatic cycle was assessed by obtaining a plateau for 75SeHCAT activity proximal to the occluding balloon, which prevented further cycles. Unabsorbed 75SeHCAT was collected after total gut washout, which was administered distal to the occluding balloon. 75SeHCAT activity in the rectal effluent measured by gamma counter was compared with that of absorbed 75SeHCAT level measured by gamma camera and was used to calculate first-pass ileal clearance. This was very efficient (mean value, 96%) and showed very little variation in the six subjects studied (range, 95%-97%). A parallel time-activity course in hepatic bile for 14C and 75Se during a single enterohepatic cycle, together with a ratio of unity for 14C/75Se in samples obtained at different time intervals, suggests that 75SeHCAT is handled by the ileum like the natural bile acid cholic acid-taurine. Extrapolation of 75SeHCAT first-pass ileal clearance to that of the natural bile acid therefore seems justifiable. In a subsidiary experiment, ileal absorption efficiency per day for 75SeHCAT was also measured by scanning the gallbladder area on 5 successive days after the measurement of first-pass ileal clearance. In contrast with absorption efficiency per cycle, absorption efficiency per day varied widely (49%-86%)

Experimental and clinical study on the digitalis in renal function disturbance

International Nuclear Information System (INIS)

Okubo, Mitsuru

1977-01-01

By using radioimmunoassay, movement of digoxin in the bodies of normal rabbits and dogs was discussed experimentally, and pathophysiology digoxin excretion in renal function disturbance was also discussed experimentally and clinically. The concentration of digoxin in each organ 30 minutes after intravenous administration of digoxin of 0.5 mg/kg to normal rabbits was the highest in the kidney, and it was high in order of skeletal muscles, ventricular muscles, and auricular muscles. A significant positive correlation was recognized between concentration of digoxin in blood and that in ventricular muscles. Digoxin clearance showed high values in normal dogs and dogs whose single kidney were extracted, when the concentration of digoxin in blood was low. A significant correlation between the concentration of digoxin in blood and BUN or creatinine was not recognized in patients with renal diseases, but a significant negative correlation between the concentration of digoxin in blood and creatinine clearance and between urinary excretion of digoxin and creatinine clearance was recognized. Therefore, creatinine clearance was thought to be useful for index to determine the administration dose of digoxin in renal dysfunction. In the patients who received external dialysis, decrease of the concentration of digoxin in blood after intravenous administration of digoxin delayed significantly in contrast to that of normal control group. (Tsunoda, M.)

Clearance of Sclerostin, Osteocalcin, Fibroblast Growth Factor 23, and Osteoprotegerin by Dialysis

DEFF Research Database (Denmark)

Carlson, Nicholas; Mortensen, Ole H.; Axelsen, Mette

2017-01-01

Introduction: Fibroblast growth factor (FGF23), sclerostin, osteocalcin, and osteoprotegerin are important factors that control mineral bone metabolism. End-stage renal disease is associated with the pronounced dysregulation of mineral bone metabolism; however, the impact and clearance of mineral...

Aspects of osseous, peritoneal and renal handling of bisphosphonate during peritoneal dialysis: a methodological study

DEFF Research Database (Denmark)

Joffe, P; Henriksen, Jens Henrik Sahl

1996-01-01

to continuous ambulatory peritoneal dialysis (CAPD). The aims were: to assess the kinetics of 99m-technetium MBP (99mTc-MBP) in CAPD, and to evaluate the correctness of the assumption that the peritoneal and renal clearances of 99mTc-MBP equal the total plasma clearance of 51-chromium ethylenediamine tetra......-acetic acid (51Cr-EDTA). Eight patients on CAPD were studied cross-sectionally. The mean plasma clearances of 99mTc-MBP and 51Cr-EDTA in the steady state (4h) were 38.2 and 12.2 ml min-1 (p peritoneal clearances (0-4 h) were 5.2 and 7.2 ml min-1 (p ....5 and 2.8 ml min-1 (not significant), respectively. The bone bisphosphonate clearance (BBC) at steady state was 26.0 ml min-1, a value which was significantly higher than that at infinity (16.5 ml min-1, p peritoneal and renal clearances of 99m...

Mechanism of renal excretion of creatinine by the pony

International Nuclear Information System (INIS)

Finco, D.R.; Groves, C.

1985-01-01

Free-flow and stop-flow procedures conducted on 2 female and 2 testosterone-treated castrated male ponies indicated that [ 14 C]inulin and exogenous creatinine clearance values were the same. These results indicated that creatinine was neither reabsorbed nor secreted by the renal tubules and that exogenous creatinine clearance was an accurate method for determining glomerular filtration rate. As in other species which have been studied, endogenous creatinine clearance probably underestimated glomerular filtration rate because of the presence of noncreatinine chromogens in plasma

Influence of renal function on the elimination of morphine and morphine glucuronides

DEFF Research Database (Denmark)

Wolff, Jesper; Bigler, Dennis Richard; Christensen, C B

1988-01-01

plasma. No significant correlation was found between total body clearance of unconjugated morphine and 51Cr-EDTA clearance. However, patients with renal insufficiency had impaired elimination of morphine glucuronides, and the apparent clearance was significantly correlated with the 51Cr-EDTA clearance (r...... = 0.94, p less than 0.001). A relatively long terminal elimination of half-life of morphine was found in all patients (mean +/- SD: 9.2 +/- 2.5 h), irrespective of glomerular function....

Drug-interaction-induced hemodynamically mediated acute renal failure in postsurgical patient

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Arup K Misra

2014-01-01

Full Text Available Acute renal failure is a life threatening condition. Nonsteroidal antiinflammatory drugs (NSAIDs and cephalosporins are widely used postoperative drugs. NSAID-induced acute renal failure has been reported in the past. In this case, drug interaction and decompensated state of the patient precipitate the condition. NSAIDs inhibit prostaglandins synthesis and thus aggravate ischemia to the kidney that is already facing volume crisis due to surgery. Due to renal dysfunction, plasma ceftriaxone level increases due to decrease clearance and it also acts as nephrotoxic by unknown mechanism. On the other hand, ceftriaxone on its interaction with diclofenac for renal tubular clearance also increases the level of diclofenac and thus further aggravate the ischemia. It is a reversible condition with excluding diclofenac from the treatment regimen and giving adequate hydration to the patient. This highlights the importance of hydration and knowledge of drugs interactions in a postsurgical patient.

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...

Renal uptake of dimercaptosuccinic acid and glomerular filtration rate in chronic nephropathy at angiotensin converting enzyme inhibition

DEFF Research Database (Denmark)

Kamper, A L; Thomsen, H S; Nielsen, S L

1990-01-01

function. Scintigrams of the kidneys showed an unaltered distribution of DMSA during treatment. GFR estimated by 51Cr-EDTA plasma clearance fell by 14% (P less than 0.01), but renal uptake of 99mTc-DMSA increased by 10% (P less than 0.01). It is concluded that DMSA in chronic renal failure is mainly taken......Glomerular filtration rate (GFR) and renal uptake of dimercaptosuccinic acid (DMSA) were measured in 31 patients with progressive chronic nephropathy before and immediately after the start of treatment with angiotensin converting enzyme (ACE) inhibitor in order to control adverse effects on kidney...

Carbamazepine and carbamazepine-10,11-epoxide clearance measurements during continuous venovenous hemofiltration in a massive overdose.

Science.gov (United States)

Smollin, Craig Geoffrey; Petrie, Matthew S; Kearney, Thomas

2016-06-01

Carbamazepine (CBZ) overdose can result in significant neurologic and cardiovascular toxicity, and is compounded by the presence of an active metabolite, carbamazepine-10,11-epoxide (CBZE). Existing publications describing continuous venovenous hemofiltration (CVVH) in CBZ overdose are limited in their ability to calculate accurate clearances. We report a case of CBZ overdose treated with CVVH with detailed measurement of CBZ, CBZE and their respective clearances calculated utilizing serial effluent measurements. This was coupled with serum level determinations comparing two analytical methodologies, time-of-flight mass spectroscopy and an immunoassay. A 41-year-old woman presented unresponsive after an overdose of CBZ. Initial CBZ serum levels were markedly elevated (57.8 μg/mL) and continued to rise. Due to continued hemodynamic instability, extracorporeal removal was initiated using CVVH. During the first 30 h of CVVH, interval serum samples and all ultrafiltrate bags were collected and analyzed. Serum and effluent levels of CBZ and CBZE were measured using an Agilent 6230 time-of-flight high-resolution mass spectrometer (TOF-MS). CBZ levels were also obtained utilizing the Microgenics CEDIA Carbamazepine Immunoassay (Thermo Fisher, Waltham, MA) for serum and effluent samples. Immunoassay analysis was performed using Siemens ADVIA 1800 instrument. The clearances achieved for CBZE (mean = 25.2, range 17.7-42.6 mL/min) exceeded that for CBZ (mean = 18.1, range 12.7-28.7 mL/min). CVVH removed a total of 1293 and 1261 mg of CBZ and CBZE, respectively. Serum levels of CBZ measured by immunoassay when compared with TOF-MS indicated cross reactivity of CBZE with the immunoassay. CVVH removed CBZE with higher clearances than CBZ. However, CVVH clearance rates for both CBZ and CBZE were lower than published clearances of CBZ and CBZE by intermittent hemodialysis. Our methodology allowed for a precise pharmacokinetic assessment of clearance based on

Rosiglitazone Affects Nitric Oxide Synthases and Improves Renal Outcome in a Rat Model of Severe Ischemia/Reperfusion Injury

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Boris Betz

2012-01-01

Full Text Available Background. Nitric oxide (NO-signal transduction plays an important role in renal ischemia/reperfusion (I/R injury. NO produced by endothelial NO-synthase (eNOS has protective functions whereas NO from inducible NO-synthase (iNOS induces impairment. Rosiglitazone (RGZ, a peroxisome proliferator-activated receptor (PPAR-γ agonist exerted beneficial effects after renal I/R injury, so we investigated whether this might be causally linked with NOS imbalance. Methods. RGZ (5 mg/kg was administered i.p. to SD-rats (f subjected to bilateral renal ischemia (60 min. Following 24 h of reperfusion, inulin- and PAH-clearance as well as PAH-net secretion were determined. Morphological alterations were graded by histopathological scoring. Plasma NOx-production was measured. eNOS and iNOS expression was analyzed by qPCR. Cleaved caspase 3 (CC3 was determined as an apoptosis indicator and ED1 as a marker of macrophage infiltration in renal tissue. Results. RGZ improves renal function after renal I/R injury (PAH-/inulin-clearance, PAH-net secretion and reduces histomorphological injury. Additionally, RGZ reduces NOx plasma levels, ED-1 positive cell infiltration and CC3 expression. iNOS-mRNA is reduced whereas eNOS-mRNA is increased by RGZ. Conclusion. RGZ has protective properties after severe renal I/R injury. Alterations of the NO pathway regarding eNOS and iNOS could be an explanation of the underlying mechanism of RGZ protection in renal I/R injury.

Role of calculated glomerular filtration rate using percutaneous nephrostomy creatinine clearance in the era of radionuclide scintigraphy

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Sunil Raghunath Patil

2017-01-01

Conclusions: GFR based on radionuclide scintigraphy may be insufficient for evaluation of residual renal function to determine the management of obstructed kidney with borderline function. For adequate decision-making, other factors including creatinine clearance via PCN should also be considered. Gates method tends to overestimate GFR as compared to calculated creatinine clearance at low GFR levels.

Predictive factors of lower calyceal stone clearance after Extracorporeal Shockwave Lithotripsy (ESWL): a focus on the infundibulopelvic anatomy.

Science.gov (United States)

Ghoneim, Islam A; Ziada, Ali M; Elkatib, Seif Eldin

2005-08-01

Controversy exists as to whether ESWL is suitable for lower pole renal stones, given the dependent position of the lower calyces. This study aims to test the effect of lower pole anatomy, namely lower polar infundibulo-pelvic angle, infundibular length and width, on clearance of fragments after ESWL. We conducted a retrospective study of 205 renal units with single lower pole stones of not more than 25 mm in their greatest diameter that were treated by ESWL alone. Exclusion criteria included multiple stones, patients requiring stenting or percutaneous drainage for various reasons. Pretreatment IVU was used to measure lower polar dimensions. Post treatment ultrasonography and KUB were used to assess clearance of fragments. The right kidney was involved in 68% and the left in 42% of cases. Average number of sessions was 1.6 with an average 3277 shockwaves per session. 134 patients (65.3%) required one session, 41 requiring 2 sessions (20%), 18 requiring 3 sessions (8.7%), 6 requiring 4 sessions (2.9%) and 8 requiring 5 sessions (3.9%). Complete clearance was attained in 141 cases, while 64 cases had residual fragments, 20 were asymptomatic and required no further management. The lower pole infundibulo-pelvic angle (LIP-A) was the most significant factor in clearance (p value 0.00001). Infundibular length (IL) was also statistically significant (p value 0.039). Lower pole anatomy has a significant impact on ESWL results. LIP-A not less than 70 degrees and an infundibular length of < 50 mm is preferable to achieve favorable outcome.

Comparative evaluation of quantitative glomerular filtration rate measured by isotopic and nonisotopic methods

International Nuclear Information System (INIS)

Balachandran, S.; Toguri, A.G.; Petrusick, T.W.; Abbott, L.C.

1981-01-01

Good correlation of glomerular filtration rate (GFR) measured isotopically from plasma disappearance of Tc-99m-DTPA (Sn) was shown with inulin clearance, creatinine clearance, and graded radionuclide imaging. The isotopic GFR is a simple, urineless technique not requiring continuous infusion that enables one to perform simultaneous renal imaging with one radiotracer

Interobserver Variation of the Renal Length Measurement on Ultrasonography

International Nuclear Information System (INIS)

Jeong, Yoong Ki; Chung, Hye Weon; Kim, Tae Sung; Ryoo, Jae Wook; Kim, Tae Kyoung; Kim, Seung Hyup

1995-01-01

We assessed interobserver variation in the measurement of the renal length on ultrasonography. Ultrasonographic examinations were performed in randomly selected 50 patients. The maximallenhths of both kidneys were measured with calipers during the scanning from frozen images by three observers in a blinded fashion. There was a relatively constant tendency of an observer to measure a renal length either longer or shorter than the other observer(Kendall coefficient>0.05). Average interobserver variations were 0.51 cm (±0.42 cm) in right kidney and 0.53 cm (±0.41 cm) in left kidney and were within 1 cm in 91% right and 89% of left kidney. Interobserver variation about 1cm should be considered in the measurement of the renal length on ultrasonography

Relationship between the thickness of the renal cortex and age: study with CT measurement

International Nuclear Information System (INIS)

Xu Yufeng; Tang Guangjian

2004-01-01

Objective: To study the relationship between the renal cortical thickness and age, and to establish the range of the normal renal cortex thickness by using CT measurement in different age groups so as to obtain a best age-related and practicable method for clinical measurement. Methods: (1) the accuracy of measuring renal cortical thickness by CT was evaluated: 18 kidney resected due to renal neoplasm were studied and the cortical thickness of the normal part of these specimens was assessed. The difference between the renal cortical thickness of specimens and preoperative measurements of renal cortex of the same patient by contrast enhanced CT was analyzed statistically. (2) 120 patients without history of renal disease or long term usage of potentially renal toxic drugs or history of hypertension were examined by CT with indication (s) other than renal disease. All the patients were divided into 20-40, 41-60, and 61-80 year-old groups. The renal cortical and parenchymal thickness and renal size were measured in three CT sections. The difference of the measurements among the three groups and their relationship to age was analyzed statistically. Results: There was no significant difference between the renal cortical thickness measured by enhanced spiral CT and measured in renal specimens (t=0.80, P=0.43). The renal cortical thickness in three groups was 0.73 cm, 0.65 cm, and 0.53 cm, respectively, and the differences among the three groups were significant (F=93.430, P 0.05). Conclusion: The measurement of the renal cortical thickness with enhanced spiral CT was reliable and was a sensitive method in investigating the morphologic changes of the kidney. The renal cortical thickness of normal kidney diminishes with age, but the change of the ratio of thickness of renal cortex to renal parenchyma with age was not significant

Severe hypothyroidism masquerading as renal impairment

DEFF Research Database (Denmark)

Bistrup, C; Jensen, Dorte Møller; Kvetny, J

1996-01-01

creatinine clearance and proteinuria, polymyositis with secondary glomerulopathy was suspected. Meanwhile, biopsies from skin, muscle, and kidney were normal. All symptoms disappeared 3 months after thyroid replacement therapy was initiated. S-TSH should be considered when evaluating patients with renal...

Glomerular filtration values obtained with 99mTc-DTPA v/s measurements of creatinine Clearance and calculation of the filtered glomerular using the Schwartz formula in a pediatric population

International Nuclear Information System (INIS)

Opazo, Claudio; Gutierrez, Elisa; Zamorano, Julio; Troncoso, TM

2005-01-01

We compare glomerular filtration rate by DTPA Renogram (DTPA-GFR) with creatinine clearance (CC) and Glomerular filtration rate from Schwartz formula (Schwartz-GFR). The need for using (DTPA-GFR) method raised from the practical difficulties in getting an accurate (CC) in pediatric population. From Sep-2001 to May-2005, 48 patients aged 1month to 18 years, underwent (DTPA-GFR) and (Schwartz-GFR). 18 had also (CC). Comparison were made among these measurements also accounting for age groups. We found a better correlation between (DTPA-GFR) and (CC) Pearson = 0,895. (Schwartz)/(CC) comparison showed a slightly lower correlation Pearson = 0,857. The worst correlation was found comparing (DTPA-GFR)/(Schwartz-GFR) in children < 3 yr Pearson = 0,560. As we found a better correlation between (DTPA-GFR)/(CC) than (DTPA-GFR)/(Schwartz-GFR), DTPA-GFR could be considered reliable method in evaluating renal function in children having difficulties to get a Creatinine Clearance (au)

Tc-99m glucoheptonate (GHA) renal uptake: Influence of biochemical and physiologic factors

International Nuclear Information System (INIS)

Lee, H.B.; Blaufox, M.D.

1984-01-01

Tc-99m-GHA is widely used for renal imaging but little is known about its handling by the kidney. Simultaneous single injection clearances of Tc-99m-GHA and I-125 Iothalamate were performed on 60 Sprague-Dawley female rats divided among six groups: I Control; II Dehydrated; III Mannitol infusion; IV Probenecid; V Alkaline urine (sodium bicarbonate); and VI Acid urine (ammonium chloride). Plasma concentration and urine excretion were followed during 80 minutes post injection. The livers and kidneys were removed and counted 120 minutes post injection. Total clearance of GHA was lower than Iothalamate in controls (0.90 +- 0.24 S.D. ml/min/100gr vs 1.47 +- 0.18, p < 0.005) but clearance of the protein free supernate was higher (1.67 +- 0.28 p=N.S.) raising a possibility of degree of tubular secretion. Unlike Tc-99m-Dimercaptosuccinic acid (DMSA) acidification of the urine appeared to have no effect on the amount of GHA in the urine (66.1 +- 6.35% Inj. dose vs 67.19 +- 6.05 p=n.s.) and hepatic uptake was minimal in all groups averaging less than 1%. Kidney uptake of GHA was 11.16 +- 1.53 (% Inj. dose) in controls. This varied slightly among groups but was markedly reduced by Probenecid blockade (4.08 +- 1.75, p < 0.0005). It appears that liver uptake of GHA is minimal, the non-protein bound fraction is freely filtered and its clearance correlates significantly with the GFR. Importantly renal accumulation of GHA is blocked by probenecid suggesting that it is actively concentrated in the proximal tubule by the enzyme system involved in PAH and Hippuran transport. It thus appears that measurement of renal function with GHA represents a different aspect of function than DMSA

Use of nonsteroidal anti-inflammatory drugs and renal failure in nursing home residents-results of the study "Inappropriate Medication in Patients with Renal Insufficiency in Nursing Homes".

Science.gov (United States)

Dörks, Michael; Herget-Rosenthal, Stefan; Schmiemann, Guido; Hoffmann, Falk

2016-04-01

Use of potentially inappropriate medications may result in increased morbidity, mortality and resource utilisation. Due to polypharmacy and age-related decline in renal function the elderly population is at particular risk. Therefore, the Beers Criteria include use of nonsteroidal anti-inflammatory drugs in chronic renal failure stage 4 and 5 as these drugs may worsen renal function. According to the summary of product characteristics, the nonsteroidal anti-inflammatory drugs ibuprofen and diclofenac are contraindicated in these patients. Objective was to assess the extent of nonsteroidal anti-inflammatory drug use in nursing homes with a focus on residents with severe renal failure. Multi-centre cross-sectional study in 21 German nursing homes. The study population comprised residents for whom at least one serum creatinine value and information about sex were available, so that creatinine clearance rate could be estimated. In all, 685 of 852 residents were included as they fulfilled the abovementioned criteria. Renal failure was severe (estimated creatinine clearance rate renal failure (20.8 %). With one exception, all residents prescribed nonsteroidal anti-inflammatory drugs with severe renal failure were treated with at least one nonsteroidal anti-inflammatory drug that was contraindicated due to the underlying renal function. Notwithstanding their classification as potentially inappropriate medications and underlying contraindications, use of nonsteroidal anti-inflammatory drugs is common among nursing home residents with severe renal failure.

Lack of effect of non-steroid antiinflammatory drugs on lithium clearance and on delivery of tubular fluid to the loop of Henle in rats.

Science.gov (United States)

Lassen, E; Thomsen, K; Sørensen, S S; Pedersen, E B

1986-11-01

This paper examines a possible interaction between non-steroid antiinflammatory drugs (NSAI drugs) and renal lithium clearance in conscious, unoperated rats with diabetes insipidus (Brattleboro strain) and ordinary Wistar rats. The drugs were given with the food for 5 days before clearance determinations in the following daily doses per kg body weight: acetylsalicyclic acid 115 mg/kg, phenylbutazone 20 mg/kg, indomethacin 5 mg/kg, and penicillamine 65 mg/kg. None of the drugs affected the lithium clearance. Also urine flow, sodium clearance, potassium clearance, and prostaglandin E2 excretion remained unaffected by the treatments. The results suggest that a continued lowering of lithium clearance cannot be produced, at least not by administration of the drugs with the food. Since lithium clearance is a quantitative measure of the delivery of tubular fluid from the proximal tubules to the loop of Henle, the results also suggest that chronic administration of NSAI drugs does not influence delivery from the proximal tubules in rats. The lowering of lithium clearance observed by others after administration of the drugs by injection or by gastric tube may have been transient, lasting only for a short period after each administration.

Radioisotope examination of the renal function in gravidic pyelonephritis

Energy Technology Data Exchange (ETDEWEB)

Voigt, R; Stoll, W; Arndt, J [Friedrich-Schiller-Universitaet, Jena (German Democratic Republic). Radiologische Klinik und Poliklinik

1980-08-01

By means of the results of combined renal sequence scintigraphy and /sup 131/I-hippurate clearance in 18 pregnant women with gravidic pyelonephritis as well as in 22 voluntary healthy pregnant women of the corresponding duration of pregnancy and in 13 non-pregnant women without hormonal anticonception as control groups the detection of the renal function with the clinical picture of gravidic pyelonephritis is discussed. The clearance equivalents are represented globally as well as subdivided to the single kidney. Besides typical activity-time curves of the control groups are demonstrated. It was shown that at the time of the most frequent occurrence of gravidic pyelonephritis in the 7th-8th month of pregnancy the clearance equivalents are decreased compared to those of uncomplicated pregnancy. The changes in the course of activity-time curves manifest themselves in a decreased initial phase as well as in an increased excretory phase. Conclusions are drawn for the clinical preliminary diagnosis of risky pregnancies from the results discussed regarding further references.

Radioisotope examination of the renal function in gravidic pyelonephritis

International Nuclear Information System (INIS)

Voigt, R.; Stoll, W.; Arndt, J.

1980-01-01

By means of the results of combined renal sequence scintigraphy and 131 I-hippurate clearance in 18 pregnant women with gravidic pyelonephritis as well as in 22 voluntary healthy pregnant women of the corresponding duration of pregnancy and in 13 non-pregnant women without hormonal anticonception as control groups the detection of the renal function with the clinical picture of gravidic pyelonephritis is discussed. The clearance equivalents are represented globally as well as subdivided to the single kidney. Besides typical activity-time curves of the control groups are demonstrated. It was shown that at the time of the most frequent occurrence of gravidic pyelonephritis in the 7th-8th month of pregnancy the clearance equivalents are decreased compared to those of uncomplicated pregnancy. The changes in the course of activity-time curves manifest themselves in a decreased initial phase as well as in an increased excretory phase. Conclusions are drawn for the clinical preliminary diagnosis of risky pregnancies from the results discussed regarding further references. (author)

Studies of the mechanism of contralateral polyuria after renal artery stenosis.

Science.gov (United States)

Galvez, O G; Roberts, B W; Mishkind, M H; Bay, W H; Ferris, T F

1977-01-01

Acute renal artery stenosis in hydropenic dogs caused a contralateral increase in urine volume and free water clearance without change in glomerular filtration, renal blood flow, or osmolar clearance. The increase in urine volume was not dependent on the development of hypertension since it occurred in animals pretreated with trimethaphan but was dependent upon angiotensin since it was presented with angiotensin blockade with Saralasin. The effect was not caused by angiotensin inhibiting antidiuretic hormone release since the polyuria occurred in hypophysectomized animals receiving a constant infusion of 10 muU/kg per min of aqueous Pitressin. Since the rise in urine volume was associated with an increase in renal vein prostaglandin E concentration and was prevented by pretreatment with indomethacin (5 mg/kg) the results suggest that the rise in plasma angiotensin after renal artery stenosis causes an increase in contralateral prostaglandin E synthesis with resultant antagonism to antidiuretic hormone at the collecting tubule. PMID:845253

Padronização do método para cálculo da captação renal absoluta do99mTc-DMSA em cria Standardization of a method to calculate absolute renal uptake of 99mTc-DMSA in children

Directory of Open Access Journals (Sweden)

Carla Rachel Ono

2006-02-01

Full Text Available OBJETIVO: O trabalho teve por objetivo padronizar o método e estabelecer valores normais da captação renal absoluta do99mTc-DMSA em crianças. MATERIAIS E MÉTODOS: Vinte e duas crianças (idade de 7 meses a 10 anos; média de 4,5 anos sem doença renal prévia foram submetidas a cintilografia renal estática com 99mTc-DMSA. Dezoito apresentavam ultra-sonografia, uretrocistografia miccional, "clearance" de creatinina e padrão visual da cintilografia renal estática normais. Quatro crianças foram excluídas por não terem completado ou por apresentarem redução do "clearance" de creatinina. A captação absoluta de DMSA (DMSA-Abs foi calculada como a porcentagem da atividade administrada retida em cada rim após seis horas da administração do radiofármaco. RESULTADOS: Os valores de DMSA-Abs foram de 21,8% ± 3,2% para o rim direito e de 23,1% ± 3,3% para o rim esquerdo. Os valores da captação absoluta não mostraram correlação com a idade dos pacientes estudados, apesar da tendência de aumento do "clearance" de creatinina com a idade. CONCLUSÃO: A definição de valores normais da DMSA-Abs permite o emprego deste parâmetro na avaliação inicial e acompanhamento de doenças renais, principalmente em pacientes com acometimento bilateral ou com rim único (nos quais a função diferencial direita X esquerda tem valor limitado.OBJECTIVE: To standardize a method and determine normal values for absolute renal uptake of 99mTc-DMSA in children with normal creatinine clearance. MATERIALS AND METHODS: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years without clinical evidence of renal disease were studied using 99mTc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99mTc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance

Lipoprotein lipase activity and chylomicron clearance in rats fed a high fat diet

International Nuclear Information System (INIS)

Brown, C.M.; Layman, D.K.

1988-01-01

The relationships of tissue and plasma lipoprotein lipase (LPL) activities to tissue uptake and plasma clearance of 14 C-labeled chylomicron-triglyceride ( 14 C-CM-TG) were studied in female rats fed isoenergetic and isonitrogenous control (12% kJ from fat) or high fat diets (72% kJ from fat) for 8 wk. Animals fed the high-fat diet had higher levels of fasting plasma triglycerides and lower LPL activities in heart, renal adipose tissue and post-heparin plasma. Changes in LPL activities of skeletal muscles varied among muscles with higher values in the soleus and plantaris (32-61%) and no differences in the gastrocnemius. The lower LPL activity in renal adipose tissue was associated with lower uptake of fatty acids from 14 C-CM-TG by adipose. Fatty-acid uptake from labeled TG was not associated with tissue LPL activity in other tissues. Clearance of 14 C-CM-TG from plasma and the half-lives of 14 C-CM-TG were similar in both dietary groups. These data indicate that tissue and plasma LPL activities are not a direct index of uptake of fatty acids by tissues or clearance of chylomicron triglycerides

Endothelial mineralocorticoid receptor ablation does not alter blood pressure, kidney function or renal vessel contractility

DEFF Research Database (Denmark)

Laursen, Sidsel B.; Finsen, Stine; Marcussen, Niels

2018-01-01

afferent arterioles. Urinary sodium excretion was determined by use of metabolic cages. EC-MR transgenics had markedly decreased MR expression in isolated aortic endothelial cells as compared to littermates (WT). Blood pressure and effective renal plasma flow at baseline and following AngII infusion...... vasculature and examined this by ablating the Nr3c2 gene in endothelial cells (EC-MR) in mice. Blood pressure, heart rate and PAH clearance were measured using indwelling catheters in conscious mice. The role of the MR in EC on contraction and relaxation was investigated in the renal artery and in perfused......Aldosterone blockade confers substantial cardiovascular and renal protection. The effects of aldosterone on mineralocorticoid receptors (MR) expressed in endothelial cells (EC) within the renal vasculature have not been delineated. We hypothesized that lack of MR in EC may be protective in renal...

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...

Renal, metabolic, and hormonal responses to proteins of different origin in normotensive, nonproteinuric type I diabetic patients.

Science.gov (United States)

Kontessis, P A; Bossinakou, I; Sarika, L; Iliopoulou, E; Papantoniou, A; Trevisan, R; Roussi, D; Stipsanelli, K; Grigorakis, S; Souvatzoglou, A

1995-09-01

Whether the differences in renal function found in vegetarian compared with omnivorous subjects are related to quantity or quality of the protein is unknown. We have studied the renal function of nine normotensive, nonproteinuric type I diabetic patients who were fed in random order for 4 weeks either an animal protein diet (APD) (protein intake 1.1 g . kg-1 . day-1) or a vegetable protein diet VPD (protein intake 0.95 g . kg-1 . day-1). The two diets were isocaloric. In a crossover study, we measured glomerular filtration rate (GFR) (inulin clearance), renal plasma flow (RPF) (p-aminohippurate clearance), plasma amino acids, growth hormone, glucagon, insulin-like growth factor I-(IGF-I), and microalbuminuria. GFR and RPF were lower with the VPD than with the APD (89.9 +/- 4.1 vs. 105.6 +/- 5.1 ml . min-1 . 1.73 m-2, P protein intake in normotensive type I diabetic patients. This could be explained partly by differences in plasma concentrations of amino acids and IGF-I.

Reversal deterioration of renal function accompanied with primary hypothyrodism

Directory of Open Access Journals (Sweden)

Dragović Tamara

2012-01-01

Full Text Available Introduction. Hypothyroidism is often accompanied with decline of kidney function, or inability to maintain electrolyte balance. These changes are usually overlooked in everyday practice. Early recognition of this association eliminates unnecessary diagnostic procedures that postpone the adequate treatment. Case report. Two patients with elevated serum creatinine levels due to primary autoimmune hypothyroidism, with complete recovery of creatinine clearance after thyroid hormone substitution therapy are presented. The first patient was a young male whose laboratory tests suggested acute renal failure, and the delicate clinical presentation of reduced thyroid function. The second patient was an elderly woman with a history of a long-term signs and symptoms attributed to ageing, including the deterioration of renal function, with consequently delayed diagnosis of hypothyroidism. Conclusion. Serum thyrotropin and thyroxin levels measurement should be done in all cases of renal failure with undefined renal desease, even if the typical clinical presentation of hypothyroidism is absent. Thyroid hormone assays sholud also be performed in all patients with chronic kidney disease whose kidney function is rapidly worsening.

Influence of renal dysfunction on the accuracy of procalcitonin for the diagnosis of postoperative infection after vascular surgery.

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Amour, Julien; Birenbaum, Aurélie; Langeron, Olivier; Le Manach, Yannick; Bertrand, Michèle; Coriat, Pierre; Riou, Bruno; Bernard, Maguy; Hausfater, Pierre

2008-04-01

Procalcitonin has been advocated as a specific biomarker for bacterial infection. We performed this study to determine whether accuracy of procalcitonin for diagnosis of postoperative bacterial infection is affected by renal function after aortic surgery. Single-center prospective study. University hospital. Two hundred seventy-six patients scheduled for elective major aortic surgery. Blood samples were taken before surgery and each day over the 5-day postoperative period, and measurement of serum procalcitonin was performed. Diagnosis of infection was performed by a blinded expert panel. Renal function was assessed using an estimate of creatinine clearance with the Cockcroft formulas. Renal dysfunction was defined as a creatinine clearance <50 mL x min(-1). Infection was diagnosed in 67 patients. Seventy five patients (27%) had postoperative renal dysfunction. Procalcitonin was significantly higher in infected patients, with a peak reached at the fourth postoperative day, but it was significantly higher in patients with impaired renal function in both control and infected patients. The optimal threshold of procalcitonin markedly differed in patients with renal dysfunction compared with patients without renal dysfunction (2.57 vs. 0.80 ng x mL(-1), p < .05). The diagnostic accuracy of procalcitonin significantly increased (0.74 vs. 0.70, p < .05) when the threshold of procalcitonin was adapted to the renal function. The elevation of procalcitonin occurred 2 days before the medical team was able to diagnose infection. Procalcitonin is a valuable marker of bacterial infections after major aortic surgery, but renal function is a major determinant of procalcitonin levels and thus different thresholds should be applied according to renal function impairment.

Noninvasive measurement of an index of renal blood flow

International Nuclear Information System (INIS)

Powers, T.A.; Rees, R.S.; Bowen, R.D.

1983-01-01

A new technique for the noninvasive measurement of an index of renal blood flow is described. The method utilizes ultrasound determined renal volume and radionuclide assessment of the mean transit time of a pertechnetate bolus through the kidneys. From this information a value for flow is calculated according to compartmental analysis principles. There is good correlation between renal blood flow estimated by this technique and that determined by microsphere injection

Vesicoureteral refluxed volume and renal function

International Nuclear Information System (INIS)

Markovic, V.; Capkun, V.; Eterovic, D.; Stanicic, A.; Saraga, M.

1994-01-01

The therapeutical approach to vesicoureteral reflux (VUR) depends on assessment of the renal involvement. The effective renal plasma flow (ERPF) and parenchymal mean transit time of radiotracer (pMTT) of the affected kidney are sensitive functional parameters. We investigated the association of these functional indices with the volume of refluxed urine. In 64 children (mean age 6.4 yrs) the presence of VUR was confirmed with direct radionuclide cystography in 80 ureters (48 unilateral and 32 bilateral) and the maximal volume of refluxed urine (MVRU) was determined for each uretero-renal unit. All patients also underwent dynamic renal scintigraphy with I-131-hippuran, providing the values of pMTT and relative renal hippuran clearances of the respective kidneys by deconvolution analysis. In 37 of the affected kidneys ERPF was also determined by combining the latter results with total ERPF, determined by plasma clearance of hippuran. Using the borderline value of MVRU of 4 ml, the group with higher MVRU exhibited significantly lower ERPF of the affected kidney (194±93 vs. 270±77 ml/min/1.73 m2, p=.002) and significantly higher proportion of pMTT's over 3.5 min (31/33 vs. 17/47, p=.003). The negative linear correlation between MVRU and ERPF was found (r=-.45, p=.006). We conclude that quantitative radionuclide cystography, aside from diagnosis and follow-up of VUR, may also provide insight in the function of the affected kidney and thus contribute in designing the therapeutical approach. (author)

Clinical nuclear medicine applications in Turkey and specific renal studies

International Nuclear Information System (INIS)

Erbas, B.

2004-01-01

Full text: Nuclear cardiology, nuclear oncology, pediatric nuclear medicine and nuclear endocrinology are the main application areas of clinical nuclear medicine in Turkey. Not only imaging studies, but also therapeutic application of radiopharmaceuticals is also performed at many institutes, such as hyperthyroidism treatment with radioiodine, thyroid cancer ablation and metastases treatment with radioiodine, radio synovectomy, metastatic pain therapy, and recently radioimmunotherapy of lymphomas. Almost all radionuclides and radiopharmaceuticals are obtained commercially from European countries, except 18-FDG which is obtained from two cyclotrons in Turkey. More than 30.000 renal procedures are performed at the University hospitals in a year. Pediatric age groups is approximately % 55 of patients. 99mTc-DTPA (%44), 99mTc-DMSA (%37), 99mTc-MAG3 (%17) and 99mTc-EC (%2) are the most commonly used radiopharmaceuticals for renal imaging. More than 6.000 vials of several pharmaceuticals are used for renal cortical scintigraphy (%35), dynamic renal imaging (%34), renal scintigraphy with diuretic (%27) and captopril scintigraphy (%4). Most common indication for renal cortical scintigraphy is detection of cortical scarring (%53). In addition, using single plasma sample method or gamma-camera method renal clearance measurements with 99mTc-MAG3 99mTc-DTPA have been used at some institutions

Clinical nuclear medicine applications in Turkey and specific renal studies

International Nuclear Information System (INIS)

Erbas, B.

2004-01-01

Nuclear cardiology, nuclear oncology, pediatric nuclear medicine and nuclear endocrinology are the main application areas of clinical nuclear medicine in Turkey. Not only imaging studies, but also therapeutic application of radiopharmaceuticals is also performed at many institutes, such as hyperthyroidism treatment with radioiodine, thyroid cancer ablation and metastases treatment with radioiodine, radio synovectomy, metastatic pain therapy, and recently radioimmunotherapy of lymphomas. Almost all radionuclides and radiopharmaceuticals are obtained commercially from European countries, except 18-FDG which is obtained from two cyclotrons in Turkey. More than 30.000 renal procedures are performed at the University hospitals in a year. Pediatric age groups is approximately % 55 of patients. 99m Tc-DTPA (%44), 99m Tc-DMSA (%37), 99m Tc-MAG3 (%17) and 99m Tc-EC (%2) are the most commonly used radiopharmaceuticals for renal imaging. More than 6.000 vials of several pharmaceuticals are used for renal cortical scintigraphy (%35), dynamic renal imaging (%34), renal scintigraphy with diuretic (%27) and captopril scintigraphy (%4). Most common indication for renal cortical scintigraphy is detection of cortical scarring (%53). In addition, using single plasma sample method or gamma-camera method renal clearance measurements with 99m Tc-MAG3 99m Tc-DTPA have been used at some institutions. (author)

Cardiovascular, endocrine and renal effects of urodilatin in normal humans

DEFF Research Database (Denmark)

Bestle, M.H.; Olsen, N.V.; Christensen, P.

1999-01-01

remained below 0.1%. The results indicate that even moderately natriuretic doses of urodilatin exert protracted effects on systemic hemodynamic, endocrine, and renal functions, including decreases in cardiac output and renal blood flow, without changes in arterial pressure or glomerular filtration rate......Effects of urodilatin (5, 10, 20, and 40 ng. kg-1. min-1) infused over 2 h on separate study days were studied in eight normal subjects with use of a randomized, double-blind protocol. All doses decreased renal plasma flow (hippurate clearance, 13-37%) and increased fractional Li+ clearance (7......-22%) and urinary Na+ excretion (by 30, 76, 136, and 99% at 5, 10, 20, and 40 ng. kg-1. min-1, respectively). Glomerular filtration rate did not increase significantly with any dose. The two lowest doses decreased cardiac output (7 and 16%) and stroke volume (10 and 20%) without changing mean arterial blood...

Functional dynamic MR imaging and pharmacokinetics of Gd-DTPA in patients with renal failure

International Nuclear Information System (INIS)

Krestin, G.P.; Neufang, K.F.R.; Friedmann, G.; Clauss, W.; Schuhmann-Giampieri, G.; Stoeckl, B.

1989-01-01

This paper reports excretion of Gd-DTPA analyzed in 20 patients with renal parenchymal disease and decreased creatinine clearance (20-80 mL/min) and compared with excretion in five patients with normal renal function. All 25 underwent a dynamic MR study that employed fast gradient-echo sequences with single images during breath holding. The time between appearance of the contrast agent in the renal cortex and signal intensity drop in the medulla was an indicator of glomerular filtration rate and correlated well with creatinine clearance values. Fractionate urine collection and serum analysis up to 120 hours showed a prolonged but complete (98%) elimination of Gd-DTPA. Renal functional parameters did not change after administration of Gd-DTPA, and no nephrotoxic effects were observed. Thus, MR imaging provides a good quantitative evaluation of the glomerular filtration rate; moreover, administration of Gd-DTPA in patients with renal failure does not impair excretory function and can therefore be safely applied in patients with reduced excretory function

The detailed measurement of foot clearance by young adults during stair descent.

Science.gov (United States)

Telonio, A; Blanchet, S; Maganaris, C N; Baltzopoulos, V; McFadyen, B J

2013-04-26

Foot clearance is an important variable for understanding safe stair negotiation, but few studies have provided detailed measures of it. This paper presents a new method to calculate minimal shoe clearance during stair descent and compares it to previous literature. Seventeen healthy young subjects descended a five step staircase with step treads of 300 mm and step heights of 188 mm. Kinematic data were collected with an Optotrak system (model 3020) and three non-colinear infrared markers on the feet. Ninety points were digitized on the foot sole prior to data collection using a 6 marker probe and related to the triad of markers on the foot. The foot sole was reconstructed using the Matlab (version 7.0) "meshgrid" function and minimal distance to each step edge was calculated for the heel, toe and foot sole. Results showed significant differences in minimum clearance between sole, heel and toe, with the shoe sole being the closest and the toe the furthest. While the hind foot sole was closest for 69% of the time, the actual minimum clearance point on the sole did vary across subjects and staircase steps. This new method, and the findings on healthy young subjects, can be applied to future studies of other populations and staircase dimensions. Copyright © 2013 Elsevier Ltd. All rights reserved.

MR measures of renal perfusion, oxygen bioavailability and total renal blood flow in a porcine model: noninvasive regional assessment of renal function.

Science.gov (United States)

Wentland, Andrew L; Artz, Nathan S; Fain, Sean B; Grist, Thomas M; Djamali, Arjang; Sadowski, Elizabeth A

2012-01-01

Magnetic resonance imaging (MRI) may be a useful adjunct to current methods of evaluating renal function. MRI is a noninvasive imaging modality that has the ability to evaluate the kidneys regionally, which is lacking in current clinical methods. Other investigators have evaluated renal function with MRI-based measurements, such as with techniques to measure cortical and medullary perfusion, oxygen bioavailability and total renal blood flow (TRBF). However, use of all three techniques simultaneously, and therefore the relationships between these MRI-derived functional parameters, have not been reported previously. To evaluate the ability of these MRI techniques to track changes in renal function, we scanned 11 swine during a state of hyperperfusion with acetylcholine and a saline bolus and subsequently scanned during a state of hypoperfusion with the prolonged use of isoflurane anesthesia. For each time point, measurements of perfusion, oxygen bioavailability and TRBF were acquired. Measurements of perfusion and oxygen bioavailability were compared with measurements of TRBF for all swine across all time points. Cortical perfusion, cortical oxygen bioavailability, medullary oxygen bioavailability and TRBF significantly increased with the acetylcholine challenge. Cortical perfusion, medullary perfusion, cortical oxygen bioavailability and TRBF significantly decreased during isoflurane anesthesia. Cortical perfusion (Spearman's correlation coefficient = 0.68; P renal function. Maintenance of the medullary oxygen bioavailability in low blood flow states may reflect the autoregulation particular to this region of the kidney. The ability to non-invasively measure all three parameters of kidney function in a single MRI examination and to evaluate the relationships between these functional parameters is potentially useful for evaluating the state of the human kidneys in situ in future studies.

Glomerular filtration rate estimated from the uptake phase of 99mTc-DTPA renography in chronic renal failure

DEFF Research Database (Denmark)

Petersen, L J; Petersen, J R; Talleruphuus, U

1999-01-01

The purpose of the study was to compare the estimation of glomerular filtration rate (GFR) from 99mTc-DTPA renography with that estimated from the renal clearance of 51Cr-EDTA, creatinine and urea.......The purpose of the study was to compare the estimation of glomerular filtration rate (GFR) from 99mTc-DTPA renography with that estimated from the renal clearance of 51Cr-EDTA, creatinine and urea....

Homer W. Smith's contribution to renal physiology.

Science.gov (United States)

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.

Uses and limitations of renal scintigraphy in renal transplantation monitoring

International Nuclear Information System (INIS)

Heaf, J.G.; Iversen, J.

2000-01-01

The value of thrice weekly technetium-99m mercaptoacetyltriglycine renography after renal transplantation was investigated in 213 consecutive transplants. A grading system was used: 0 = normal renogram; 1 = normal uptake, reduced excretion; 2 = normal uptake, flat excretion curve; 3 = rising curve; 4 = reduced rate of uptake, rising curve and reduced absolute uptake; 5 = minimal uptake. The initial renogram grade (RG) was primarily a marker of ischaemic damage, being poorer with cadaver donation, long cold ischaemia (>24 h), and high donor and recipient age. High primary RG predicted primary graft non-function, long time to graft function, low discharge Cr EDTA clearance and low 1- and 5-year graft survival. Discharge RG predicted late (>6 months) graft loss. RG was highly correlated (P<0.001) with creatinine and creatinine clearance, and changes in RG were correlated with changes in renal function. A change in RG of 0.5 was non-specific, while a change of 1 or more predicted clinical complications in 95% of cases. The negative predictive value was low (58%). RG change antedated clinical diagnosis in only 38% of cases, and in only 14% of acute rejections did an RG change of 1 or more antedate a rising creatinine. RG did not contribute to the differential diagnosis between acute rejection, acute tubulointerstitial nephropathy and cyclosporine toxicity. In conclusion, an initial renography after transplantation is valuable as it measures ischaemic damage and predicts duration of graft non-function and both short and long-term graft survival. A review of the literature suggests that the indication for serial scintigraphic monitoring for functioning grafts is less certain: the diagnostic specificity is insufficient for it to be the definitive investigation for common diagnostic problems and it does not give sufficient advance warning of impending problems. (orig.)

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)

Regional cerebral blood flow measurements using noninvasive 133Xe clearance method in children

International Nuclear Information System (INIS)

Nishimoto, Hiroshi; Maeda, Koji; Kagawa, Yukihide; Morozumi, Kunihiko; Hashimoto, Manami; Tsubokawa, Takashi.

1985-01-01

The noninvasive 133-Xe clearance method of estimating rCBF has been widely used in adult clinical studies. It is safe, noninvasive and reproducible, and has provided valuable insight into adult cerebrovascular pathophysiology. However, in children, this technique has not been used to measure rCBF for some fundamental problems. This study was performed to clarify these fundamental problems for applications of noninvasive 133-Xe clearance technique to children. The results showed that three fundamental problems concerning; (1) volume of dead spaces in airway circuits of the system, (2) increasing of look-through phenomenon and (3) correction methods for recirculated 133-Xe and airway artifacts to estimate rCBF are important for applications to children. These problems should be improved to measure as correct rCBF in children as in adults. (author)

Tc-99m mercaptoacetylglycine to evaluate renal damage after ESWL

International Nuclear Information System (INIS)

Schaub, T.; Witsch, U.; El Damanhoury, H.; Naegele-Woehrle, B.; Hahn, K.

1990-01-01

This paper evaluates renal damage after extracorporeal shock wave lithotripsy (ESWL) with a new Tc-99m renal imaging compound. Tc-99m mercaptoacetylglycine-3 (MAG3) sequential scintigraphy was performed on 113 patients. A gamma camera was used, and the studies were done within 2 days before and after ESWL for renal stones. Relative renal function and clearance were calculated. Seventy (62%) of the 113 patients had abnormal findings after ESWL that were not present before the treatment. In 56 patients (50%) intra- or perirenal lesions were seen on sequential scintigraphy. Forty-six patients (41%) had a decrease of the relative renal function of at least 3% without an increase of total renal function

Development of the clearance level verification evaluation system. 2. Construction of the clearance data management system

International Nuclear Information System (INIS)

Kubota, Shintaro; Usui, Hideo; Kawagoshi, Hiroshi

2014-06-01

Clearance is defined as the removal of radioactive materials or radioactive objects within authorized practices from any further regulatory control by the regulatory body. In Japan, clearance level and a procedure for its verification has been introduced under the Laws and Regulations, and solid clearance wastes inspected by the national authority can be handled and recycled as normal wastes. The most prevalent type of wastes have generated from the dismantling of nuclear facilities, so the Japan Atomic Energy Agency (JAEA) has been developing the Clearance Level Verification Evaluation System (CLEVES) as a convenient tool. The Clearance Data Management System (CDMS), which is a part of CLEVES, has been developed to support measurement, evaluation, making and recording documents with clearance level verification. In addition, validation of the evaluation result of the CDMS was carried out by inputting the data of actual clearance activities in the JAEA. Clearance level verification is easily applied by using the CDMS for the clearance activities. (author)

Determination of hepatic fractional clearance of radioactive gold colloids for a measure of effective hepatic blood flow

International Nuclear Information System (INIS)

Fujii, Masahiro

1979-01-01

For a measure of effective blood flow, a hepatic fractional clearance of 198 Au-colloids was determined, which was obtained from the disappearance rate multiplied by the fraction of injected dose taken up by the liver. The hepatic uptake was determined with a gamma camera. The counts over the liver was corrected for body weight and height. The method was considered sufficiently simple for routine use. 198 Au-colloids were obtained from Dainabot Lab. and CIS. The former gave 64% higher values of disappearance rate than the latter, without any change in the organ distribution. A quality control tests were applied over a six-year period to the disappearance rates. Reproducibility within 95 to confidence limits was found for both groups. In 28 normal control subjects, hepatic fractional clearance of the colloids from Dainabot Lab. was 18.5 +- 3.4%/min. In patients with progressed hepatic disease, both hepatic fractional clearance and final hepatic uptake were decreased, showing that the determination of hepatic uptake is necessary in measuring effective hepatic blood flow by the colloidal clearance method. The influence of splenic uptake is discussed in relation to hepatic blood flow measurement. (author)

An Optical Fiber Bundle Sensor for Tip Clearance and Tip Timing Measurements in a Turbine Rig

Directory of Open Access Journals (Sweden)

María Asunción Illarramendi

2013-06-01

Full Text Available When it comes to measuring blade-tip clearance or blade-tip timing in turbines, reflective intensity-modulated optical fiber sensors overcome several traditional limitations of capacitive, inductive or discharging probe sensors. This paper presents the signals and results corresponding to the third stage of a multistage turbine rig, obtained from a transonic wind-tunnel test. The probe is based on a trifurcated bundle of optical fibers that is mounted on the turbine casing. To eliminate the influence of light source intensity variations and blade surface reflectivity, the sensing principle is based on the quotient of the voltages obtained from the two receiving bundle legs. A discrepancy lower than 3% with respect to a commercial sensor was observed in tip clearance measurements. Regarding tip timing measurements, the travel wave spectrum was obtained, which provides the average vibration amplitude for all blades at a particular nodal diameter. With this approach, both blade-tip timing and tip clearance measurements can be carried out simultaneously. The results obtained on the test turbine rig demonstrate the suitability and reliability of the type of sensor used, and suggest the possibility of performing these measurements in real turbines under real working conditions.

A computerized system for handling renal size measurements from urograms

International Nuclear Information System (INIS)

Claesson, I.; Jacobsson, B.F.; Riha, M.

1987-01-01

The size of a kidney, as measured on an urogram, is a sensitive indicator of renal damage in a child with urinary tract infection, and renal surface area correlates well with glomerular filtration rate. Sequential measurements can be invaluable in evaluating the efficacy of a regimen of treatment. A system utilizing a personal microcomputer has been developed to facilitate the measuring procedure and the handling and analysis of data. (orig.)

Renal scintiscanning: Methodology and normal findings using 131I hippurane and a gamma camera

International Nuclear Information System (INIS)

Ruppik, G.

1982-01-01

The methodological and mathematical fundamentals of renal functional scintiscanning using a gamma camera and 131 I-hippurane are described for ING, whole-body clearance, plasma clearance, and unilateral clearance. Methods are compared introducing the Tuebingen method of unilateral clearance with tolerance limits. The data of the patients are presented as standard values with a limit of two standard deviations for whole-body clearance unilateral clearance, the parenchymal phase and the excretion phase including a percentage of excretion. Comparative studies are presented for the main parameters of clearance and unilateral clearance, and the data obtained are documented in tables and graphs together with the initial data and the standard values. The results and problems of the method are gone into. (orig./MG) [de

Population pharmacokinetics of pomalidomide in patients with relapsed or refractory multiple myeloma with various degrees of impaired renal function.

Science.gov (United States)

Li, Yan; Wang, Xiaomin; O'Mara, Edward; Dimopoulos, Meletios A; Sonneveld, Pieter; Weisel, Katja C; Matous, Jeffrey; Siegel, David S; Shah, Jatin J; Kueenburg, Elisabeth; Sternas, Lars; Cavanaugh, Chloe; Zaki, Mohamed; Palmisano, Maria; Zhou, Simon

2017-01-01

Pomalidomide is an immunomodulatory drug for treatment of relapsed or refractory multiple myeloma (rrMM) in patients who often have comorbid renal conditions. To assess the impact of renal impairment on pomalidomide exposure, a population pharmacokinetics (PPK) model of pomalidomide in rrMM patients with various degrees of impaired renal function was developed. Intensive and sparse pomalidomide concentration data collected from two clinical studies in rrMM patients with normal renal function, moderately impaired renal function, severely impaired renal function not requiring dialysis, and with severely impaired renal function requiring dialysis were pooled over the dose range of 2 to 4 mg, to assess specifically the influence of the impaired renal function as a categorical variable and a continuous variable on pomalidomide clearance and plasma exposure. In addition, pomalidomide concentration data collected on dialysis days from both the withdrawal (arterial) side and from the returning (venous) side of the dialyzer, from rrMM patients with severely impaired renal function requiring dialysis, were used to assess the extent to which dialysis contributes to the removal of pomalidomide from blood circulation. PPK analyses demonstrated that moderate to severe renal impairment not requiring dialysis has no influence on pomalidomide clearance or plasma exposure, as compared to those patients with normal renal function, while pomalidomide exposure increased approximately 35% in patients with severe renal impairment requiring dialysis on nondialysis days. In addition, dialysis increased total body pomalidomide clearance from 5 L/h to 12 L/h, indicating that dialysis will significantly remove pomalidomide from the blood circulation. Thus, pomalidomide should be administered post-dialysis on the days of dialysis.

Biomarker for early renal microvascular and diabetic kidney diseases.

Science.gov (United States)

Futrakul, Narisa; Futrakul, Prasit

2017-11-01

Recognition of early stage of diabetic kidney disease, under common practice using biomarkers, namely microalbuminuria, serum creatinine level above 1 mg/dL and accepted definition of diabetic kidney disease associated with creatinine clearance value below 60 mL/min/1.73 m 2 , is unlikely. This would lead to delay treatment associated with therapeutic resistance to vasodilator due to a defective vascular homoeostasis. Other alternative biomarkers related to the state of microalbuminuria is not sensitive to screen for early diabetic kidney disease (stages I, II). In this regard, a better diagnostic markers to serve for this purpose are creatinine clearance, fractional excretion of magnesium (FE Mg), cystatin C. Recently, renal microvascular disease and renal ischemia have been demonstrated to correlate indirectly with the development of diabetic kidney disease and its function. Among these are angiogenic and anti-angiogenic factors, namely VEGF, VEGF receptors, angiopoietins and endostatin. With respect to therapeutic prevention, implementation of treatment at early stage of diabetic and nondiabetic kidney disease is able to restore renal perfusion and function.

The feasibility of measuring renal blood flow using transesophageal echocardiography in patients undergoing cardiac surgery.

Science.gov (United States)

Yang, Ping-Liang; Wong, David T; Dai, Shuang-Bo; Song, Hai-Bo; Ye, Ling; Liu, Jin; Liu, Bin

2009-05-01

There is no reliable method to monitor renal blood flow intraoperatively. In this study, we evaluated the feasibility and reproducibility of left renal blood flow measurements using transesophageal echocardiography during cardiac surgery. In this prospective noninterventional study, left renal blood flow was measured with transesophageal echocardiography during three time points (pre-, intra-, and postcardiopulmonary bypass) in 60 patients undergoing cardiac surgery. Sonograms from 6 subjects were interpreted by 2 blinded independent assessors at the time of acquisition and 6 mo later. Interobserver and intraobserver reproducibility were quantified by calculating variability and intraclass correlation coefficients. Patients with Doppler angles of >30 degrees (20 of 60 subjects) were eliminated from renal blood flow measurements. Left renal blood flow was successfully measured and analyzed in 36 of 60 (60%) subjects. Both interobserver and intraobserver variability were renal blood flow measurements were good to excellent (intraclass correlation coefficients 0.604-0.999). Left renal arterial luminal diameter for the pre, intra, and postcardiopulmonary bypass phases, ranged from 3.8 to 4.1 mm, renal arterial velocity from 25 to 35 cm/s, and left renal blood flow from 192 to 299 mL/min. In patients undergoing cardiac surgery, it was feasible in 60% of the subjects to measure left renal blood flow using intraoperative transesophageal echocardiography. The interobserver and intraobserver reproducibility of renal blood flow measurements was good to excellent.

Intensified Multifactorial Intervention in Type 2 Diabetes and Microalbuminuria Reduces End Stage Renal Disease and Mortality

DEFF Research Database (Denmark)

Oellgaard, Jens; Gæde, Peter; Rossing, Peter

2016-01-01

-label trial. Duration of the intervention was 8 years, where after all patients were recommended intensified treatment. Total follow-up of up to 21 years of 24 hour urinary albumin excretion rate and GFR (51Cr-EDTA-clearance) assessed at 6 study visits. Information on end stage renal disease (ESRD......) and mortality was obtained from national registries. Outcome measures were progression to macroalbuminuria (>300 mg/24h), decline-rates of GFR and progression to end stage renal disease (ESRD) or death. Results: Progression to macroalbuminuria was reduced in the original intensive-therapy group with a hazard...

Measurement of contact angle in a clearance-fit pin-loaded hole

Science.gov (United States)

Prabhakaran, R.; Naik, R. A.

1986-01-01

A technique which measures load-contact variation in a clearance-fit, pin-loaded hole is presented in detail. A steel instrumented pin, which activates a make-or-break electrical circuit in the pin-hole contact region, was inserted into one aluminum and one polycarbonate specimen. The resulting load-contact variations are indicated schematically. The ability to accurately determine the arc of contact at any load was crucial to this measurement. It is noted that this simple experimental technique is applicable to both conducting and nonconducting materials.

Clearance measurements as a tool for waste minimization during decommissioning

International Nuclear Information System (INIS)

Konneus, Patrick; Andersson, Veronica; Lindberg, Maria

2012-01-01

Clearance, exemption or free release of material from regulatory control are three ways of expressing the same thing, minimizing the amount of waste that needs disposal as radioactive waste and therefor preserving a repository as a national asset. Studsvik Nuclear has utilized the former full body measurement cell as a shielded compartment used for gamma spectroscopy measurements of materials that may be subject to clearance. The cell was moved from its original position by heavy lifting and transport, as it was transported in one piece weighing 53 tonnes. The facility has basically 4 parts, the cell in which the item is place, the rotating table that rotates the item to get the best possible measurement, the ISOCS that measure the gamma rays and the operator room from which the facility runs. The detector is a BEGe with a relative efficiency of 50 % and is provided by Canberra. Apex is used as software for acquisition, calibration and data storage. The cell can take Bergloefs boxes up to a volume of 1.2m 3 and a weight of 3 tonnes can be rotated on the table. Other standard geometries are drums of 100 or 200 liters. The shielding improves the background radiation to a level where a measurement time of only 1200 s for a standard object (100 L/200 L drum, Bergloefs box) is needed. This means a high daily capacity of measurements. During 2011 measurements have been done on several different materials and together with sampling for alpha emitting nuclides the material has been released from regulatory control and either recycled or disposed of in a standard landfill or a land fill for hazardous waste. The materials released are copper from cable shredding that was measured, samples and recycled about 14 tonnes, titanium tubes about 35 tonnes also recycled and fiberglass/epoxy that has been released for waste treatment in a non-radioactive treatment facility. Measurements have also been done of waste with complex geometries. (authors)

Comparative study of unilateral renal tubule function using 131I-o-hippuran and sup(99m)Tc-dimercaptosuccinic acid with regard to renal depth and excretion relations

International Nuclear Information System (INIS)

Moser, E.A.

1980-01-01

Good agreement was found between sonographic and nuclear renal depth data. In patients with undisturbed postrenal urodynamics, the data of unilateral renal clearance obtained by DMSA and OIH are in good agreement after depth correction. With OIH, the activity measured for unilateral congestion kidneys was higher than with DMSA. However, both methods may overestimate unilateral congestion kidneys. The OIH method should be favoured in nuclear renal diagnostics. In patients with mobile kidneys, the lower function calculated for the ptotic kidney can be evaluated only after depth correction. To reduce the radiation exposure, renal depth data required for depth correction should be determined by sonographic methods. The peak/scatter method of renal depth determination cannot be employed in practice in the 131 J hippurane test; in the sup(99m)Tc-DMSA test, sufficient agreement between peak/scatter quotient and renal depth is only obtained after background correction. The result does not warrant the tedious procedure. DMSA studies of the kidneys are appropriate in the following cases: 1. Emergency studies of unilateral renal function in cases of acute anuria due to postrenal stoppage. 2. Assessment of unilateral parenchymal function in patients with mobile kidneys if the ptotic kidney cannot be imaged by sonographic processes. 3. Search for extremely displaced renal tissue. 4. Unilateral renal function studies in patients with unilateral kidney diseases if the postrenal situation and the global renal function can be assessed by other methods. (orig./MG) [de

Angiography for renal artery stenosis: no additional impairment of renal function by angioplasty

Energy Technology Data Exchange (ETDEWEB)

Lufft, Volkmar; Fels, Lueder M.; Egbeyong-Baiyee, Daniel; Olbricht, Christoph J. [Abteilung Nephrologie, Medizinische Hochschule Hannover (Germany); Hoogestraat-Lufft, Linda; Galanski, Michael [Abteilung Diagnostische Radiologie, Medizinische Hochschule Hannover (Germany)

2002-04-01

The aim of this study was to compare renal function between patients with renal angiography and patients with renal angiography and angioplasty (AP) for renal artery stenosis (RAS). Forty-seven patients with suspected RAS were prospectively investigated by digital subtraction angiography (DSA) using non-ionic low osmolar contrast media (CM). In 22 patients RAS was detected and in 16 cases an angioplasty was performed in the same session. The following parameters were determined 1 day prior to and after the DSA, respectively: serum creatinine (S-Crea, {mu}mol/l) and single-shot inulin clearance (In-Cl, ml/min) for the evaluation of renal function; and urine alpha 1-microglobuline (AMG, {mu}g/g Crea) and beta-N-acetyl-glucoseaminidase (beta-NAG, U/g Crea) as markers of tubular toxicity. Serum creatinine was measured additionally 2 days after CM had been injected. In both groups with and without AP 174{+-}65 and 104{+-}56 ml of CM (p<0.0005) were used, respectively. There were no differences with regard to renal function or risk factors for CM nephrotoxicity between both groups. In the group with AP S-Crea and In-Cl (each: mean{+-}SD) did not change significantly (before DSA: 171{+-}158 and 61{+-}24, after DSA: 189{+-}177 and 61{+-}25, respectively), beta-NAG (median) rose from 4 to 14 (p<0.05) and AMG from 8 to 55 (n.s., because of high SD). In the group without AP S-Crea increased from 134{+-}109 to 141{+-}113 (p<0.01), In-Cl dropped from 65{+-}26 to 62{+-}26 (p<0,01), beta NAG (median) rose from 4 to 8 (p=0.01), and AMG from 7 to 10 (n.s.). A rise in baseline S-Crea by more than 25% or 44 {mu}mol/l occurred in 4 and 2 patients in the group with and without AP, respectively. Creatinine increase was reversible in all cases within 7 days. In this study using sensitive methods to detect changes of renal function and tubular toxicity no additional renal function impairment in DSA with angioplasty for RAS compared with DSA alone could be demonstrated. Our data suggest

Iohexol plasma clearance measurement in older adults with chronic kidney disease-sampling time matters.

Science.gov (United States)

Ebert, Natalie; Loesment, Amina; Martus, Peter; Jakob, Olga; Gaedeke, Jens; Kuhlmann, Martin; Bartel, Jan; Schuchardt, Mirjam; Tölle, Markus; Huang, Tao; van der Giet, Markus; Schaeffner, Elke

2015-08-01

Accurate and precise measurement of GFR is important for patients with chronic kidney disease (CKD). Sampling time of exogenous filtration markers may have great impact on measured GFR (mGFR) results, but there is still uncertainty about optimal timing of plasma clearance measurement in patients with advanced CKD, for whom 24-h measurement is recommended. This satellite project of the Berlin Initiative Study evaluates whether 24-h iohexol plasma clearance reveals a clinically relevant difference compared with 5-h measurement in older adults. In 104 participants with a mean age of 79 years and diagnosed CKD, we performed standard GFR measurement over 5 h (mGFR300) using iohexol plasma concentrations at 120, 180, 240 and 300 min after injection. With an additional sample at 1440 min, we assessed 24-h GFR measurement (mGFR1440). Study design was cross-sectional. Calculation of mGFR was conducted with a one compartment model using the Brochner-Mortensen equation to calculate the fast component. mGFR values were compared with estimated GFR values (MDRD, CKD-EPI, BIS1, Revised Lund-Malmö and Cockcroft-Gault). In all 104 subjects, mGFR1440 was lower than mGFR300 (23 ± 8 versus 29 ± 9 mL/min/1.73 m(2), mean ± SD; P clearance up to 5 h leads to a clinically relevant overestimation of GFR compared with 24-h measurement. In clinical care, this effect should be bore in mind especially for patients with considerably reduced GFR levels. A new correction formula has been developed to predict mGFR1440 from mGFR300. For accurate GFR estimates in elderly CKD patients, we recommend the Revised Lund Malmö equation. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Association of ABCB1 genetic variants with renal function in Africans and in Caucasians

Directory of Open Access Journals (Sweden)

Elston Robert C

2008-06-01

Full Text Available Abstract Background The P-glycoprotein, encoded by the ABCB1 gene, is expressed in human endothelial and mesangial cells, which contribute to control renal plasma flow and glomerular filtration rate. We investigated the association of ABCB1 variants with renal function in African and Caucasian subjects. Methods In Africans (290 subjects from 62 pedigrees, we genotyped the 2677G>T and 3435 C>T ABCB1 polymorphisms. Glomerular filtration rate (GFR was measured using inulin clearance and effective renal plasma flow (ERPF using para-aminohippurate clearance. In Caucasians (5382 unrelated subjects, we analyzed 30 SNPs located within and around ABCB1, using data from the Affymetrix 500 K chip. GFR was estimated using the simplified Modification of the Diet in Renal Disease (MDRD and Cockcroft-Gault equations. Results In Africans, compared to the reference genotype (GG or CC, each copy of the 2677T and 3435T allele was associated, respectively, with: GFR higher by 10.6 ± 2.9 (P P = 0.06 mL/min; ERPF higher by 47.5 ± 11.6 (P P = 0.007 mL/min; and renal resistances lower by 0.016 ± 0.004 (P P = 0.004 mm Hg/mL/min. In Caucasians, we identified 3 polymorphisms in the ABCB1 gene that were strongly associated with all estimates of GFR (smallest P value = 0.0006, overall P = 0.014 after multiple testing correction. Conclusion Variants of the ABCB1 gene were associated with renal function in both Africans and Caucasians and may therefore confer susceptibility to nephropathy in humans. If confirmed in other studies, these results point toward a new candidate gene for nephropathy in humans.

Estimating glomerular filtration rate: Cockcroft-Gault and Modification of Diet in Renal Disease formulas compared to renal inulin clearance.

NARCIS (Netherlands)

Botev, R.; Mallie, J.P.; Couchoud, C.; Schuck, O.; Fauvel, J.P.; Wetzels, J.F.M.; Lee, N.; Santo, N.G. De; Cirillo, M.

2009-01-01

BACKGROUND AND OBJECTIVES: Evaluation of renal function by estimation of the glomerular filtration rate (GFR) is very important for the diagnosis and treatment of patients with chronic kidney disease (CKD). The Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) formulas are the

Aldosterone dysregulation with aging predicts renal vascular function and cardiovascular risk.

Science.gov (United States)

Brown, Jenifer M; Underwood, Patricia C; Ferri, Claudio; Hopkins, Paul N; Williams, Gordon H; Adler, Gail K; Vaidya, Anand

2014-06-01

Aging and abnormal aldosterone regulation are both associated with vascular disease. We hypothesized that aldosterone dysregulation influences the age-related risk of renal vascular and cardiovascular disease. We conducted an analysis of 562 subjects who underwent detailed investigations under conditions of liberal and restricted dietary sodium intake (1124 visits) in the General Clinical Research Center. Aldosterone regulation was characterized by the ratio of maximal suppression to stimulation (supine serum aldosterone on a liberal sodium diet divided by the same measure on a restricted sodium diet). We previously demonstrated that higher levels of this Sodium-modulated Aldosterone Suppression-Stimulation Index (SASSI) indicate greater aldosterone dysregulation. Renal plasma flow (RPF) was determined via p-aminohippurate clearance to assess basal renal hemodynamics and the renal vascular responses to dietary sodium manipulation and angiotensin II infusion. Cardiovascular risk was calculated using the Framingham Risk Score. In univariate linear regression, older age (β=-4.60; Page and SASSI, where the inverse relationship between SASSI and RPF was most apparent with older age (Page may interact to mediate renal vascular disease. Our findings suggest that the combination of aldosterone dysregulation and renal vascular dysfunction could additively increase the risk of future cardiovascular outcomes; therefore, aldosterone dysregulation may represent a modifiable mechanism of age-related vascular disease.

Evaluation of serum iohexol clearance for use in predicting carboplatin clearance in cats.

Science.gov (United States)

Bailey, Dennis B; Rassnick, Kenneth M; Prey, Joshua D; Dykes, Nathan L

2009-09-01

To determine whether a glomerular filtration rate (GFR) assay based on serum iohexol clearance can be used to predict carboplatin clearance in cats. 10 cats with tumors. GFR was measured concurrently by use of plasma clearance of technetium Tc 99m-labeled diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) to yield GFR(99mTc-DTPA) and serum clearance of iohexol to yield GFR(Iohexol). A single dose of carboplatin was administered IV as a bolus. Dose was calculated by use of a target value for the area under the plasma platinum concentration-versus-time curve (AUC(Target)) and estimation of platinum clearance (CL(PT)) derived from GFR(99mTc-DTPA) as follows: dose = AUC(Target) x 2.6 x GFR(99mTc-DTPA) x body weight, where AUC(Target) is 2.75 min.mg.mL(-1). Plasma platinum concentrations were measured via atomic absorption spectrophotometry. Values for GFR(99mTc-DTPA) and GFR(Iohexol) were compared by use of least-squares regression and Bland-Altman analysis. Least-squares regression was used to determine whether CL(PT) could be predicted from GFR(99mTc-DTPA) or GFR(Iohexol) (or both). GFR(99mTc-DTPA) and GFR(Iohexol) were strongly correlated (r = 0.90), but GFR(Iohexol) values were significantly larger by a factor of approximately 1.4. Platinum clearance had a significant linear relationship to GFR(99mTc-DTPA) (CL(PT) = 2.5 x GFR(99mTc-DTPA)) and to GFR(Iohexol) (CL(PT) = [1.3 x GFR(Iohexol)] + 1.4). In cats, serum iohexol clearance was an accurate predictor of CL(PT) and can be used to calculate the carboplatin dose as follows: dose = AUC(Target) x ([1.3 x GFR(Iohexol)] + 1.4) x body weight.

Clearance measurement for waste concerning contained radioactivity; Frei(gabe)messung von Abfall hinsichtlich enthaltener Radioaktivitaet

Energy Technology Data Exchange (ETDEWEB)

Sokcic-Kostic, Marina; Schultheis, Roland [NUKEM Technologies Engineering Services GmbH, Alzenau (Germany)

2016-12-15

Clearance measurements are always a compromise between requirements of the measurement technology and economic boundary conditions. Depending on the quantity and the type of waste, different solutions are obtained. For large volumes of more or less homogeneous waste, the conveyor belt method is the biggest favorite, which has already proved its suitability in practice. This is important, because numerous nuclear power stations are being decommissioned in Germany in the coming years and large quantities of waste will be arising. For some applications, e.g. Tritium or C-14, satisfying solutions either do not exist or are currently in the development stages. There is still great potential for the development of clearance methods.

Novel lanthanide-labeled metal oxide nanoparticles improve the measurement of in vivo clearance and translocation

Directory of Open Access Journals (Sweden)

Abid Aamir D

2013-01-01

Full Text Available Abstract The deposition, clearance and translocation of europium-doped gadolinium oxide nanoparticles in a mouse lung were investigated experimentally. Nanoparticles were synthesized by spray flame pyrolysis. The particle size, crystallinity and surface properties were characterized. Following instillation, the concentrations of particles in organs were determined with inductively coupled plasma mass spectrometry. The protein corona coating the nanoparticles was found to be similar to the coating on more environmentally relevant nanoparticles such as iron oxide. Measurements of the solubility of the nanoparticles in surrogates of biological fluids indicated very little propensity for dissolution, and the elemental ratio of particle constituents did not change, adding further support to the contention that intact nanoparticles were measured. The particles were intratracheally instilled into the mouse lung. After 24 hours, the target organs were harvested, acid digested and the nanoparticle mass in each organ was measured by inductively coupled plasma mass spectrometry (ICP-MS. The nanoparticles were detected in all the studied organs at low ppb levels; 59% of the particles remained in the lung. A significant amount of particles was also detected in the feces, suggesting fast clearance mechanisms. The nanoparticle system used in this work is highly suitable for quantitatively determining deposition, transport and clearance of nanoparticles from the lung, providing a quantified measure of delivered dose.

Clinical benefits of using inulin clearance and cystatin C for determining glomerular filtration rate in HIV-1-infected individuals treated with dolutegravir.

Science.gov (United States)

Yukawa, Satomi; Watanabe, Dai; Uehira, Tomoko; Shirasaka, Takuma

2018-03-01

Dolutegravir may inhibit creatinine transporters in renal tubules and elevate serum creatinine levels. We investigated the usefulness of glomerular filtration rate (GFR) measured using inulin clearance (Cin), creatinine clearance (Ccr), and estimated GFR based on both serum creatinine (eGFRcre) and serum cystatin C (eGFRcys). HIV-1-infected Japanese patients with suppressed viremia and whose antiretroviral drug was switched to dolutegravir from other drugs were included (n = 108, Study 1). We compared eGFRcre and eGFRcys at the start and after 48 weeks of dolutegravir administration. For the patients providing consent, we measured Cin and Ccr (n = 15, Study 2). We assessed biases and accuracy and compared Cin with eGFRcre, eGFRcys, and Ccr. There were no differences in serum cystatin C and eGFRcys between baseline and at 48 weeks. Moreover, eGFRcre was significantly less accurate (within 30% of measured GFR) than both eGFRcys and Ccr (40% accuracy compared to 93% and 93%, respectively). eGFRcys was significantly less biased than eGFRcre and Ccr (p inulin clearance and eGFRcys. This is the first study performing inulin clearance for HIV-1-infected individuals and to show data for eGFRcys from a large cohort following a switch to dolutegravir from other antiretroviral agents. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of hypercholesterolemia of renal hemodynamics: study in patients with nephrotic syndrome.

Science.gov (United States)

Fuiano, G; Esposito, C; Sepe, V; Colucci, G; Bovino, M; Rosa, M; Balletta, M; Bellinghieri, G; Conte, G; Cianciaruso, B; Dal Canton, A

1996-01-01

Experimental and clinical studies have demonstrated a positive relationship between hyperlipidemia and rate of progression of renal disease, suggesting that lipids can induce or aggravate glomerular injury mainly by interacting with mesangial cells. Nevertheless, recently has been demonstrated that increased cholesterol levels can also induce endothelial cell dysfunction. Thus, since endothelium is known to play a major role in modulating the vascular tone, we have tested the possibility that hypercholesterolemia impairs the renal hemodynamics in patients with active nephrotic syndrome and elevated serum cholesterol levels. In this single-blind, nonrandom study, 12 patients were treated with pravastatin (group T, treated, n = 12) and 8 with placebo (group C, controls, n = 8). The controls were studied after the pravastatin group had been completed. Before starting the treatment the patients underwent basal determinations including routine laboratory investigations and PAH and inulin clearances. The same determinations were repeated after 48 h, and 6 and 12 weeks from the beginning of the treatment. The study at 48 h was performed to see if pravastatin had a direct, cholesterol-independent effect on renal function. The following basal results were reported (mean +/- SEM; group T vs. group C): serum cholesterol (mmol/l) 9.7 +/- 0.4 vs. 9.1 +/- 0.3 (NS); proteinuria (g/24 h): 6.2 +/- 0.2 vs. 7.0 +/- 0.7 (NS); PAH clearance (ml/min): 353 +/- 21 vs. 385 +/- 31 (NS); inulin clearance (ml/min): 62.5 +/- 7.7 vs. 67 +/- 9.3 (NS). After 48 h, no changes were observed in both groups. Subsequently, in group T, the following percentage changes of basal levels were observed: serum cholesterol -21.4 +/- 3.2% at 6 weeks (p < 0.05) and -34.9 +/- 3.2% at 12 weeks (p < 0.01); inulin clearance +3 +/- 3.7% at 6 weeks (NS) and +9.3 +/- 2.9% at 12 weeks (p < 0.05); PAH clearance +7 +/- 3.1% at 6 weeks (p < 0.05) and +21.2 +/- 5.5% at 12 weeks (p < 0.01). By contrast, no significant

Improvement in Creatinine Clearance after Open Heart Surgery in Infants as an Early Indicator of Surgical Success.

Science.gov (United States)

Dagan, Amit; Dagan, Ovadia

2016-12-01

Early surgical correction of congenital heart malformations in neonates and small infants may be complicated by acute kidney injury (AKI), which is associated with higher morbidity and mortality rates, especially in patients who require dialysis. Glomerular filtration rate (GFR) is considered the best measurement of renal function which, in neonates and infants, is highly dependent on heart function. To determine whether measurements of creatinine clearance after open heart surgery in neonates and young infants can serve as an early indicator of surgical success or AKI. We conducted a prospective observational study in 19 neonates and small infants (body weight creatinine clearance and albumin excretion was performed before and during surgery and four times during 48 hours after surgery. Mean creatinine clearance was lowest during surgery (25.2 ± 4. ml/min/1.73 m2) and increased significantly in the first 16 hours post-surgery (45.7 ± 6.3 ml/min/1.73 m2). A similar pattern was noted for urine albumin which was highest during surgery (203 ± 31 µg/min) and lowest (93 ± 20 µg/min) 48 hours post-surgery. AKI occurred in four patients, and two patients even required dialysis. All six showed a decline in creatinine clearance and an increase in urine albumin between 8 and 16 hours post-surgery. In neonates and small infants undergoing open heart surgery, a significant improvement in creatinine clearance in the first 16 hours postoperatively is indicative of a good surgical outcome. This finding has important implications for the early evaluation and treatment of patients in the intensive care unit on the first day post-surgery.

Clinical evaluation of renal function study using I-123 orthoiodohippurate (I-123 OIH) in patients with obstructive uropathy

International Nuclear Information System (INIS)

Okada, Junichi; Uchiyama, Guio; Katsurai, Hiroshi; Uno, Koichi; Uematsu, Sadao.

1984-01-01

Functional images and regional renograms using I-123 OIH were evaluated by comparing with patients' clinical courses, intravenous pyelographies and Creatinine clearances. Twenty-one patients with obstructive uropathy were studied. Functional images were processed in three parameters of Tmax, T 1/2 and ERBF (effective renal blood flow). ERBF images were composed of regional counts in early blood flow phase of renograms. Regional renograms were produced on renal parenchyma and pelvis. ERBF images represented the functioning distributions of renal tissue after the surgery and the recoveries in the renal parenchyma. Tmax and T 1/2 images and pelvic regional renograms showed the good correlations with IVP findings which presented the dilatation of pelvis and the delay of excretion. Parenchymal regional renograms showed the poor correlations with Creatinine clearances and caused sometimes errors in ROI settings. The evaluation of renal function only by the parenchymal regional renogram seemed to be inappropriated. (author)

High-NaCl diet impairs dynamic renal blood flow autoregulation in rats with adenine-induced chronic renal failure

DEFF Research Database (Denmark)

Saeed, Aso; DiBona, Gerald F; Grimberg, Elisabeth

2014-01-01

This study examined the effects of 2 wk of high-NaCl diet on kidney function and dynamic renal blood flow autoregulation (RBFA) in rats with adenine-induced chronic renal failure (ACRF). Male Sprague-Dawley rats received either chow containing adenine or were pair-fed an identical diet without...... arterial pressure variability (SAPV), and heart rate variability were assessed by spectral analytical techniques. Rats with ACRF showed marked reductions in glomerular filtration rate and renal blood flow (RBF), whereas mean arterial pressure and SAPV were significantly elevated. In addition, spontaneous...... adenine (controls). After 10 wk, rats were randomized to either remain on the same diet (0.6% NaCl) or to be switched to high 4% NaCl chow. Two weeks after randomization, renal clearance experiments were performed under isoflurane anesthesia and dynamic RBFA, baroreflex sensitivity (BRS), systolic...

Renal function measured by X-ray fluorescence analysis

International Nuclear Information System (INIS)

Boijsen, M.; Jacobsson, L.; Tylen, U.; Sahlgrenska Sjukhuset, Goeteborg

1987-01-01

In twenty-six patients injected with metrizoate during urography, plasma was analyzed for iodine concentration using X-ray fluorescence analysis, and total plasma clearance of contrast medium was calculated. Total plasma clearance of 51 Cr-EDTA was also determined, but not simultaneously, in order to find out if the urographic procedure would influence the kidneys to such an extent that the contrast medium clearance value would differ much from the 51 Cr-EDTA clearance value. The errors in the method were assessed and the total error of the contrast medium clearance determination was calculated. When comparing 51 Cr-EDTA and metrizoate clearance a correlation of 0.94 and a mean ratio of 1.046 (SD 0.138) was found. The assessable errors cannot fully explain the standard deviation, which might indicate a transient change in kidney function related to elements of the urographic procedure such as laxation with possible dehydration and/or the contrast medium dose. (orig.)

Impact of mild renal impairment on early postoperative mortality after open cardiac surgery

International Nuclear Information System (INIS)

A Abdel Ghani; Muath Al Nasar

2010-01-01

Preoperative severe renal impairment is included in the risk scores to predict outcome after open cardiac surgery. The purpose of this study was to assess the impact of pr operative mild renal impairment on the early postoperative mortality after open heart surgery. Data of all cases of open cardiac surgery performed from January 2005 to June 2006 were collected. Cases with preoperative creatinine clearance below 60 mL/min were excluded from the study. Data were retrospectively analyzed to find the impact of renal impairment on short-term outcome. Of the 500 cases studied, 47 had preoperative creatinine clearance between 89-60 mL/min. The overall mortality in the study cases was 6.8%. The mortality was 28.7% in those who developed postoperative ARF, 33.3% in those who required dialysis and 40.8% in those with preoperative mild renal impairment. Binary logistic regression analysis showed that female gender (P = 0.01), preoperative mild renal impairment (P 0.007) as well as occurrence of multi organ failure (P < 0.001) were the only independent variables determining the early postoperative mortality after cardiac surgeries. Among them, preoperative mild renal impairment was the most significant and the best predictor for early postoperative mortality after cardiac surgery. Our study suggests that renal impairment remains a strong predictor of early mortality even after adjustment for several confounders (Author).

Mechanisms by which heme oxygenase rescue renal dysfunction in obesity

Directory of Open Access Journals (Sweden)

Joseph Fomusi Ndisang

2014-01-01

Collectively, these data suggest that hemin ameliorates nephropathy by potentiating the expression of proteins of repair/regeneration, abating oxidative/inflammatory mediators, reducing renal histo-pathological lesions, while enhancing nephrin, podocin, podocalyxin, CD2AP and creatinine clearance, with corresponding reduction of albuminuria/proteinuria suggesting improved renal function in hemin-treated ZFs. Importantly, the concomitant potentiation regeneration proteins and podocyte cytoskeletal proteins are novel mechanisms by which hemin rescue nephropathy in obesity.

Peritoneal clearances in hypertensive CAPD patients after oral administration of clonidine, enalapril, and nifedipine.

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Favazza, A; Motanaro, D; Messa, P; Antonucci, F; Gropuzzo, M; Mioni, G

1992-01-01

The authors investigated whether the reduction of arterial pressure, induced by the oral administration of clonidine (CLO), enalapril (EN), and nifedipine (NIF), has any effect on peritoneal transport rates. The study was performed in nine hypertensive patients undergoing continuous ambulatory peritoneal dialysis (CAPD). The patients were submitted to administration of CLO, EN, and NIF, each in randomized succession for two weeks, after withdrawal of any hypotensive therapy for eight days (washout period). The nine patients underwent a four-hour dwell exchange using a 2.27 g/dL glucose two-liter bag after washout and after each hypotensive period. The following parameters were analyzed: mean arterial pressure (MAP), performed in the sitting position; net ultrafiltration; effluent/initial dialysate glucose ratio (GL D/Do); peritoneal clearance of K, BUN, creatinine (Cr), phosphate, beta-2 microglobulin (beta 2), total proteins, and the ratio between beta 2 and Cr clearance. Moreover, residual renal Cr and beta 2 clearances were analyzed. The three drugs significantly reduced MAP at a similar rate. The peritoneal transport parameters after CLO were similar to the results in the washout period. On the contrary, after EN and NIF therapy, Cr and beta 2 clearances were significantly increased, and GL D/Do decreased in comparison to the washout period. The other peritoneal transport parameters after EN and NIF were similar to the washout period. Residual renal Cr and beta 2 clearances after the three drugs were similar to those in the washout. these data suggest that after two weeks of therapy with EN and NIF, glucose, Cr, and beta 2 peritoneal transports are influenced by these hypotensive drugs irrespective of the effect on the arterial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal cortical volume measured using automatic contouring software for computed tomography and its relationship with BMI, age and renal function

International Nuclear Information System (INIS)

Muto, Natalia Sayuri; Kamishima, Tamotsu; Harris, Ardene A.; Kato, Fumi; Onodera, Yuya; Terae, Satoshi; Shirato, Hiroki

2011-01-01

Purpose: To evaluate the relationship between renal cortical volume, measured by an automatic contouring software, with body mass index (BMI), age and renal function. Materials and methods: The study was performed in accordance to the institutional guidelines at our hospital. Sixty-four patients (34 men, 30 women), aged 19 to 79 years had their CT scans for diagnosis or follow-up of hepatocellular carcinoma retrospectively examined by a computer workstation using a software that automatically contours the renal cortex and the renal parenchyma. Body mass index and estimated glomerular filtration rate (eGFR) were calculated based on data collected. Statistical analysis was done using the Student t-test, multiple regression analysis, and intraclass correlation coefficient (ICC). Results: The ICC for total renal and renal cortical volumes were 0.98 and 0.99, respectively. Renal volume measurements yielded a mean cortical volume of 105.8 cm 3 ± 28.4 SD, mean total volume of 153 cm 3 ± 39 SD and mean medullary volume of 47.8 cm 3 ± 19.5 SD. The correlation between body weight/height/BMI and both total renal and cortical volumes presented r = 0.6, 0.6 and 0.4, respectively, p < 0.05, while the correlation between renal cortex and age was r = -0.3, p < 0.05. eGFR showed correlation with renal cortical volume r = 0.6, p < 0.05. Conclusion: This study demonstrated that renal cortical volume had a moderate positive relationship with BMI, moderate negative relationship with age, and a strong positive relationship with the renal function, and provided a new method to routinely produce volumetric assessment of the kidney.

Reproducibility of estimation of blood flow in the human masseter muscle from measurements of 133Xe clearance

International Nuclear Information System (INIS)

Monteiro, A.A.; Kopp, S.

1989-01-01

The reproducibility of estimations of the masseter intramuscular blood flow (IMBF) was assessed bilaterally within and between clinical sessions. The 133 Xe clearance in nine normal individuals was measured before, during, and immediately after endurance of isometric contraction at an attempted level of 50% of maximum voluntary clenching contraction. An overall low reproducibility of the estimations was found. This result was probably caused by uncertainties about the excact site of intramuscular 133 Xe deposition, errors in assessment of the plots of clearance, and variabilities in the relative contraction levels sustained, especially in the overall muscle effort. In agreement with previous reports concerning other skeletal muscles, the 133 Xe clearance method provided inconsistent estimates of absolute values of IMBF also in this clinical setting. Although there was a high intra-individual variation in the relative level of isometric contraction sustained, the endurance test induced distinct changes in IMBF, among which the estimate of post-endurance hyperemia was the most consistent for each individual. Therefore, measurements of 133 Xe clearance seem to be useful to detect intra-induvidual changes in masseter IMBF resulting from isometric work. 21 refs

Velocity and pressure measurements in guide vane clearance gap of a low specific speed Francis turbine

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Thapa, B. S.; Dahlhaug, O. G.; Thapa, B.

2016-11-01

In Francis turbine, a small clearance gap between the guide vanes and the cover plates is usually required to pivot guide vanes as a part of governing system. Deflection of cover plates and erosion of mating surfaces causes this gap to increase from its design value. The clearance gap induces the secondary flow in the distributor system. This effects the main flow at the runner inlet, which causes losses in efficiency and instability. A guide vane cascade of a low specific speed Francis turbine has been developed for experimental investigations. The test setup is able to produce similar velocity distributions at the runner inlet as that of a reference prototype turbine. The setup is designed for particle image velocimetry (PIV) measurements from the position of stay vane outlet to the position of runner inlet. In this study, velocity and pressure measurements are conducted with 2 mm clearance gap on one side of guide vane. Leakage flow is observed and measured together with pressure measurements. It is concluded that the leakage flow behaves as a jet and mixes with the main flow in cross-wise direction and forms a vortex filament. This causes non-uniform inlet flow conditions at runner blades.

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

Hypogonadism and renal failure: An update.

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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.

Renal hemodynamics in uranyl acetate-induced acute renal failure of rabbits

International Nuclear Information System (INIS)

Sudo, M.; Honda, N.; Hishida, A.; Nagase, M.

1977-01-01

The role of renal hemodynamic alterations in the curtailment of renal function was studied in rabbits with uranyl acetate-induced acute renal failure. The day following the i.v. injection of uranyl acetate (2 mg/kg of body wt), renal blood flow (RBF) and clearance of creatinine (Ccr) decreased to approximately 60 and 20% of controls, respectively. Intracortical fractional flow distribution, estimated by radioactive microsphere method, did not change. The extraction ratio of para-aminohippurate (EPAH) decreased and the renal extraction of sodium (CNa/Ccr) increased, with minimal structural change in the kidney. Urine output increased two to three times that of the control. After three days oliguria appeared despite complete recovery of RBF. The zonal flow redistributed toward the deep cortex. CCr and EPAH reached their minimums, concomitantly with tubular necrosis and intratubular casts. After seven days animals could be divided into the oliguric and diuretic groups. CCr and EPAH were higher in the diuretic group, while there was no significant difference in RBF and the flow distribution between groups. Regeneration of damaged tubular cells was found in the diuretic group but not in the oliguric group. The findings suggest the minor roles of RBF and the intracortical flow distribution, and a fundamental role of back leakage of filtrate across damaged tubular epithelium in the maintenance of reduced CCR and urine output during the oliguric stage in rabbits with uranyl acetate-induced renal failure

Neural regulation of the kidney function in rats with cisplatin induced renal failure

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Goulding, Niamh E.; Johns, Edward J.

2015-01-01

Aim: Chronic kidney disease (CKD) is often associated with a disturbed cardiovascular homeostasis. This investigation explored the role of the renal innervation in mediating deranged baroreflex control of renal sympathetic nerve activity (RSNA) and renal excretory function in cisplatin-induced renal failure. Methods: Rats were either intact or bilaterally renally denervated 4 days prior to receiving cisplatin (5 mg/kg i.p.) and entered a chronic metabolic study for 8 days. At day 8, other groups of rats were prepared for acute measurement of RSNA or renal function with either intact or denervated kidneys. Results: Following the cisplatin challenge, creatinine clearance was 50% lower while fractional sodium excretion and renal cortical and medullary TGF-β1 concentrations were 3–4 fold higher in both intact and renally denervated rats compared to control rats. In cisplatin-treated rats, the maximal gain of the high-pressure baroreflex curve was only 20% that of control rats, but following renal denervation not different from that of renally denervated control rats. Volume expansion reduced RSNA by 50% in control and in cisplatin-treated rats but only following bilateral renal denervation. The volume expansion mediated natriuresis/diuresis was absent in the cisplatin-treated rats but was normalized following renal denervation. Conclusions: Cisplatin-induced renal injury impaired renal function and caused a sympatho-excitation with blunting of high and low pressure baroreflex regulation of RSNA, which was dependent on the renal innervation. It is suggested that in man with CKD there is a dysregulation of the neural control of the kidney mediated by its sensory innervation. PMID:26175693

Determination of representative renal depth for accurate attenuation corred in measurement of glomerular filtration rate in transplanted kidney

International Nuclear Information System (INIS)

Oh, Soon Nam; Kim, Sung Hoon; Rha, Sung Eun; Chung, Yong An; Yoo, Ie Ryung; Sohn, Hyung Sun; Lee, Sung Young; Chung, Soo Kyo

2002-01-01

To measure reliable glomerular filtration rate by using the representative values of transplanted renal depths, which are measured with ultrasonography. We included 54 patients (26 men, 28 women), with having both renal scintigraphy and ultrasonography after renal transplantation. We measured DFR with Gates' method using the renal depth measured by ultrasonography, and median and mean ones in each patient. We compared GFR derived from ultrasonography-measured renal depth with GFR derived from median and mean renal depths. The correlation coefficients were obtained among GFR derived from ultrasonography-measured renal depths, median and mean renal depth under linear regression analysis. We determined whether GFR derived from median or mean renal depth could substitute GFR derived from ultrasonography-measured renal depth with Bland-Altman method. We analyze the expected errors of the GFR using representative renal depth in terms of age, sex, weight, height, creatinine value, and body surface. The transplanted renal depths range from 3.20 cm to 5.96 cm. The mean value and standard deviation of renal depths measured by ultrasonography are 4.09±0.65 cm in men, and 4.24±0.78 cm in women. The median value of renal depths measured by ultrasonography is 4.36 cm in men and 4.14 cm in women. The GFR derived from median renal depth is more consistent with GFR derived from ultrasonography-measured renal depth than GFR derived from mean renal depth. Differences of GFR derived from median and ultrasonography-measured renal depth are not significantly different in the groups classified with creatinine value, age, sex, height, weight and body surface. When median value is adapted as a representative renal depth, we could obtain reliable GFR in transplanted kidney simply

Characterization of in vitro glucuronidation clearance of a range of drugs in human kidney microsomes: comparison with liver and intestinal glucuronidation and impact of albumin.

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Gill, Katherine L; Houston, J Brian; Galetin, Aleksandra

2012-04-01

Previous studies have shown the importance of the addition of albumin for characterization of hepatic glucuronidation in vitro; however, no reports exist on the effects of albumin on renal or intestinal microsomal glucuronidation assays. This study characterized glucuronidation clearance (CL(int, UGT)) in human kidney, liver, and intestinal microsomes in the presence and absence of bovine serum albumin (BSA) for seven drugs with differential UDP-glucuronosyltransferase (UGT) 1A9 and UGT2B7 specificity, namely, diclofenac, ezetimibe, gemfibrozil, mycophenolic acid, naloxone, propofol, and telmisartan. The impact of renal CL(int, UGT) on accuracy of in vitro-in vivo extrapolation (IVIVE) of glucuronidation clearance was investigated. Inclusion of 1% BSA for acidic drugs and 2% for bases/neutral drugs in incubations was found to be suitable for characterization of CL(int, UGT) in different tissues. Although BSA increased CL(int, UGT) in all tissues, the extent was tissue- and drug-dependent. Scaled CL(int, UGT) in the presence of BSA ranged from 2.22 to 207, 0.439 to 24.4, and 0.292 to 23.8 ml · min(-1) · g tissue(-1) in liver, kidney, and intestinal microsomes. Renal CL(int, UGT) (per gram of tissue) was up to 2-fold higher in comparison with that for liver for UGT1A9 substrates; in contrast, CL(int, UGT) for UGT2B7 substrates represented approximately one-third of hepatic estimates. Scaled renal CL(int, UGT) (in the presence of BSA) was up to 30-fold higher than intestinal glucuronidation for the drugs investigated. Use of in vitro data obtained in the presence of BSA and inclusion of renal clearance improved the IVIVE of glucuronidation clearance, with 50% of drugs predicted within 2-fold of observed values. Characterization and consideration of kidney CL(int, UGT) is particularly important for UGT1A9 substrates.

Renal function after unilateral nephrectomy for Wilms' tumour: the influence of radiation therapy

International Nuclear Information System (INIS)

Graaf, S.S.N. de; Gent, H. van; Reitsma-Bierens, W.Ch.C.; Luyk, W.H.J. van; Postma, A.; Dolsma, W.V.

1996-01-01

The effect of therapy on renal function after unilateral nephrectomy for Wilms' tumour was studied. In the second year following unilateral nephrectomy, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were estimated simultaneously by measuring 125 I-iothalamate clearance and 131 I-hippurate clearance. Of 41 evaluable patients, 29 received chemotherapy as sole treatment modality following nephrectomy (group 1); 12 patients additionally received radiation therapy to a field that included the remaining kidney (group 2). Results were expressed as standard deviation scores (z-scores). In group 1, mean z-score for GFR was -0.27 (94.6% of normal) and in group 2 mean z-score was -1.51 (72.7% of normal for two kidneys) (P = 0.022, Mann-Whitney U-test). Mean z-score for ERPF was -0.09 (97.0%) in group 1 and -1.53 (73.8%) in group 2 (P 0.039). It was concluded that the combination of chemotherapy and radiation therapy, in contrast to chemotherapy alone, negatively affects the ability of the remaining kidney to adjust its function after the loss of its counterpart. (author)

Urinary aminopeptidase activities as early and predictive biomarkers of renal dysfunction in cisplatin-treated rats.

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Andrés Quesada

Full Text Available This study analyzes the fluorimetric determination of alanyl- (Ala, glutamyl- (Glu, leucyl-cystinyl- (Cys and aspartyl-aminopeptidase (AspAp urinary enzymatic activities as early and predictive biomarkers of renal dysfunction in cisplatin-treated rats. Male Wistar rats (n = 8 each group received a single subcutaneous injection of either saline or cisplatin 3.5 or 7 mg/kg, and urine samples were taken at 0, 1, 2, 3 and 14 days after treatment. In urine samples we determined Ala, Glu, Cys and AspAp activities, proteinuria, N-acetyl-β-D-glucosaminidase (NAG, albumin, and neutrophil gelatinase-associated lipocalin (NGAL. Plasma creatinine, creatinine clearance and renal morphological variables were measured at the end of the experiment. CysAp, NAG and albumin were increased 48 hours after treatment in the cisplatin 3.5 mg/kg treated group. At 24 hours, all urinary aminopeptidase activities and albuminuria were significantly increased in the cisplatin 7 mg/kg treated group. Aminopeptidase urinary activities correlated (p0.259 with plasma creatinine, creatinine clearance and/or kidney weight/body weight ratio at the end of the experiment and they could be considered as predictive biomarkers of renal injury severity. ROC-AUC analysis was made to study their sensitivity and specificity to distinguish between treated and untreated rats at day 1. All aminopeptidase activities showed an AUC>0.633. We conclude that Ala, Cys, Glu and AspAp enzymatic activities are early and predictive urinary biomarkers of the renal dysfunction induced by cisplatin. These determinations can be very useful in the prognostic and diagnostic of renal dysfunction in preclinical research and clinical practice.

Abnormalities of the breast in chronic renal failure and renal transplantation

Energy Technology Data Exchange (ETDEWEB)

Lee, Bae Young; Kim, Hak Hee; Choi, Kyu Ho; Park, Seog Hee [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)

2000-12-15

Manifestations of breast abnormalities in these patients included breast calcifications, duct dilatation, fibrocystic change, rapidly enlarged multiple fibroadenomas, edema, invasive ductal cancer, extensive fibrosis, spontaneous hemorrhage, and Mondor's disease. These interesting cases we experienced are reported. Prolactin, growth hormone, and cortisol are required concurrently for normal development of mammary epithelium. Hormonal profile of chronic renal failure is different to normal person due to decreased renal clearance. The incidence of breast cancer is also increased in CRF. Metastatic soft tissue calcification is well described finding in chronic renal failure related to an increase in serum calcium phosphate product and secondary hyperparathyroidism. Kidney failure alone may increases prolactin level. The possibility of deranged hypothalamic-pituitary control mechanisms do not excluded. Impaired prolactin response to TRH stimulation has also been observed. Methyldopa and tricyclic antidepressants specifically were associated with hyperprolactinemia. Cyclosporin administration may elevate serum prolactin levels with simultaneous down regulation of prolactin receptors. Some populations of lymphocytes and fibroblasts exhibit cyclosporin receptors. Cyclosporin could potentially promote fibroadenomas by direct action, and seems to alter LH secretion.

Abnormalities of the breast in chronic renal failure and renal transplantation

International Nuclear Information System (INIS)

Lee, Bae Young; Kim, Hak Hee; Choi, Kyu Ho; Park, Seog Hee

2000-01-01

Manifestations of breast abnormalities in these patients included breast calcifications, duct dilatation, fibrocystic change, rapidly enlarged multiple fibroadenomas, edema, invasive ductal cancer, extensive fibrosis, spontaneous hemorrhage, and Mondor's disease. These interesting cases we experienced are reported. Prolactin, growth hormone, and cortisol are required concurrently for normal development of mammary epithelium. Hormonal profile of chronic renal failure is different to normal person due to decreased renal clearance. The incidence of breast cancer is also increased in CRF. Metastatic soft tissue calcification is well described finding in chronic renal failure related to an increase in serum calcium phosphate product and secondary hyperparathyroidism. Kidney failure alone may increases prolactin level. The possibility of deranged hypothalamic-pituitary control mechanisms do not excluded. Impaired prolactin response to TRH stimulation has also been observed. Methyldopa and tricyclic antidepressants specifically were associated with hyperprolactinemia. Cyclosporin administration may elevate serum prolactin levels with simultaneous down regulation of prolactin receptors. Some populations of lymphocytes and fibroblasts exhibit cyclosporin receptors. Cyclosporin could potentially promote fibroadenomas by direct action, and seems to alter LH secretion.

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.

Initial Evaluation of (99m)Tc(CO)3(ASMA) as a Renal Tracer in Healthy Human Volunteers.

Science.gov (United States)

Lipowska, Malgorzata; Klenc, Jeffrey; Folks, Russell D; Taylor, Andrew T

2014-09-01

Preclinical studies in rats showed that two of (99m)Tc(CO)3(ASMA) isomers (rac- and L-ASMA) had pharmacokinetic properties equivalent to that of (131)I-OIH, the radiopharmaceutical standard for the measurement of effective renal plasma flow. The aim of this study was to evaluate the pharmacokinetics of (99m)Tc(CO)3(ASMA) isomers in healthy human subjects. Three ASMA ligands (rac-, L- and D-ASMA) were labeled with (99m)Tc(CO)3 using an IsoLink kit (Covidien), and each formed (99m)Tc(CO)3(ASMA) tracer was co-injected with (131)I-OIH into healthy human subjects followed by sequential imaging, plasma clearance measurements and timed urine collection. Plasma protein binding, red cell uptake and percent injected dose in the urine were determined. Urine from each group of volunteers was analyzed for metabolites by HPLC. Image quality was excellent with all three agents. Each (99m)Tc(CO)3(ASMA) preparation was excreted unchanged in the urine. The plasma clearance ratio ((99m)Tc(CO)3(ASMA)/(131)I-OIH) was 81 ± 3 % for D-ASMA compared to only 20 ± 4 % for L-ASMA and 37 ± 7 % for rac-ASMA; the 81 % clearance ratio for D-ASMA isomer is still ∼ 30 % higher than the (99m)Tc-MAG3/(131)I-OIH clearance ratio (∼50-60 %). Red cell uptake was similar for all three tracers (6-9 %), and all tracers had a relatively rapid renal excretion; at 3 h, the (99m)Tc(CO)3(ASMA)/(131)I-OIH urine ratio was 100 ± 3 % for D-ASMA, 80 ± 2 % for L-ASMA and 88 ± 1 % for rac-ASMA. The renal excretion characteristics of (99m)Tc(CO)3(D-ASMA) in humans are superior to those of the other two (99m)Tc(CO)3(ASMA) isomers studied, but are still inferior to (131)I-OIH, even though there was no difference in the clearance of two of (99m)Tc(CO)3(ASMA) isomers and (131)I-OIH in rats. The work described here demonstrates the sensitivity in in vivo biological behavior of (99m)Tc(CO)3(ASMA) isomers to their subtle structural differences.

The changes in renal function after a single dose of intravenous furosemide in patients with compensated liver cirrhosis

Directory of Open Access Journals (Sweden)

Mejirisky Yoram

2006-11-01

Full Text Available Abstract Background Patients with compensated Child-A cirrhosis have sub clinical hypovolemia and diuretic treatment could result in renal impairment. Aim To evaluate the changes in renal functional mass as reflected by DMSA uptake after single injection of intravenous furosemide in patients with compensated liver cirrhosis. Methods Eighteen cirrhotic patients were divided in two groups; eight patients (group 1, age 56 ± 9.6 yrs, Gender 5M/3F, 3 alcoholic and 5 non alcoholic were given low intravenous 40 mg furosemide and ten other patients (group 2, age 54 ± 9.9, Gender 6M/4F, 4 alcoholic and 6 non alcoholic were given high 120 mg furosemide respectively. Renoscintigraphy with 100MBq Of Tc 99 DMSA was given intravenously before and 90 minutes after furosemide administration and SPECT imaging was determined 3 hours later. All patients were kept under low sodium diet (80mEq/d and all diuretics were withdrawn for 3 days. 8-hours UNa exertion, Calculated and measured Creatinine clearance (CCT were performed for all patients. Results Intravenous furosemide increased the mean renal DMSA uptake in 55% of patients with compensated cirrhosis and these changes persist up to three hours after injection. This increase was at the same extent in either low or high doses of furosemide. (From 12.8% ± 3.8 to 15.2% ± 2.2, p 40%, as compared to normal calculated creatinine clearance (CCT 101 ± 26, and measured CCT of 87 ± 30 cc/min (P Conclusion A single furosemide injection increases renal functional mass as reflected by DMSA in 55% of patients with compensated cirrhosis and identify 45% of patients with reduced uptake and who could develop renal impairment under diuretics. Whether or not albumin infusion exerts beneficial effect in those patients with reduced DMSA uptake remains to be determined.

Mercaptoacetyltriglycine diuretic renography and output efficiency measurement in renal transplant patients

International Nuclear Information System (INIS)

Spicer, S.T.; Chi, Ka-Kit; Larcos, G.; Farlow, D.C.; Choong, K.K.L.; Gruenewald, S.M.; Nankivell, B.J.; Chapman, J.R.

1999-01-01

Suspected urinary tract obstruction following renal transplantation presents a diagnostic dilemma. The purposes of this study were: (1) to establish a normal range of measurement of output efficiency (OE) in the renal transplant population, and (2) to assess prospectively the usefulness of OE in the setting of allograft obstruction. Twenty-two renal transplant patients with stable renal function and no evidence of hydronephrosis on serial ultrasound examination had a diuretic mercaptoacetyltriglycine scan with calculation of OE. Three renal transplant patients with confirmed graft obstruction were also studied. Standard qualitative and quantitative parameters as well as OE were calculated. The mean OE for the 22 normal renal transplant patients was 86.3%±3.7% (range: 77%-91%). OE values in the three obstructed patients were 59%, 68% and 75% respectively. It is concluded that OE should normally exceed 77% in renal graft recipients. OE is a promising means of diagnosing functional obstruction in these patients. (orig.)

Use of a Microsoft Excel based add-in program to calculate plasma sinistrin clearance by a two-compartment model analysis in dogs.

Science.gov (United States)

Steinbach, Sarah M L; Sturgess, Christopher P; Dunning, Mark D; Neiger, Reto

2015-06-01

Assessment of renal function by means of plasma clearance of a suitable marker has become standard procedure for estimation of glomerular filtration rate (GFR). Sinistrin, a polyfructan solely cleared by the kidney, is often used for this purpose. Pharmacokinetic modeling using adequate software is necessary to calculate disappearance rate and half-life of sinistrin. The purpose of this study was to describe the use of a Microsoft excel based add-in program to calculate plasma sinistrin clearance, as well as additional pharmacokinetic parameters such as transfer rates (k), half-life (t1/2) and volume of distribution (Vss) for sinistrin in dogs with varying degrees of renal function. Copyright © 2015 Elsevier Ltd. All rights reserved.

High phenobarbital clearance during continuous renal replacement therapy: a case report and pharmacokinetic analysis.

Science.gov (United States)

Rosenborg, Staffan; Saraste, Lars; Wide, Katarina

2014-08-01

Phenobarbital is an old antiepileptic drug used in severe epilepsy. Despite this, little is written about the need for dose adjustments in renal replacement therapy. Most sources recommend a moderately increased dose guided by therapeutic drug monitoring.A 14 year old boy with nonketotic hyperglycinemia, a rare inborn error of metabolism, characterized by high levels of glycine, epilepsy, spasticity, and cognitive impairment, was admitted to the emergency department with respiratory failure after a few days of fever and cough. The boy was unconscious at admittance and had acute renal and hepatic failure.Due to the acute respiratory infection, hypoxic hepatic and renal failure occurred and the patient had a status epilepticus.The patient was intubated and mechanically ventilated. Continuous renal replacement therapy was initiated. Despite increased phenobarbital doses, therapeutic levels were not reached until the dose was increased to 500 mg twice daily. Therapeutic drug monitoring was performed in plasma and dialysate. Calculations revealed that phenobarbital was almost freely dialyzed.Correct dosing of drugs in patients on renal replacement therapy may need a multidisciplinary approach and guidance by therapeutic drug monitoring.

Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment.

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Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

2015-04-01

Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems. Copyright © 2015 Elsevier B.V. All rights reserved.

Angiography for renal artery stenosis: no additional impairment of renal function by angioplasty

International Nuclear Information System (INIS)

Lufft, Volkmar; Fels, Lueder M.; Egbeyong-Baiyee, Daniel; Olbricht, Christoph J.; Hoogestraat-Lufft, Linda; Galanski, Michael

2002-01-01

The aim of this study was to compare renal function between patients with renal angiography and patients with renal angiography and angioplasty (AP) for renal artery stenosis (RAS). Forty-seven patients with suspected RAS were prospectively investigated by digital subtraction angiography (DSA) using non-ionic low osmolar contrast media (CM). In 22 patients RAS was detected and in 16 cases an angioplasty was performed in the same session. The following parameters were determined 1 day prior to and after the DSA, respectively: serum creatinine (S-Crea, μmol/l) and single-shot inulin clearance (In-Cl, ml/min) for the evaluation of renal function; and urine alpha 1-microglobuline (AMG, μg/g Crea) and beta-N-acetyl-glucoseaminidase (beta-NAG, U/g Crea) as markers of tubular toxicity. Serum creatinine was measured additionally 2 days after CM had been injected. In both groups with and without AP 174±65 and 104±56 ml of CM (p<0.0005) were used, respectively. There were no differences with regard to renal function or risk factors for CM nephrotoxicity between both groups. In the group with AP S-Crea and In-Cl (each: mean±SD) did not change significantly (before DSA: 171±158 and 61±24, after DSA: 189±177 and 61±25, respectively), beta-NAG (median) rose from 4 to 14 (p<0.05) and AMG from 8 to 55 (n.s., because of high SD). In the group without AP S-Crea increased from 134±109 to 141±113 (p<0.01), In-Cl dropped from 65±26 to 62±26 (p<0,01), beta NAG (median) rose from 4 to 8 (p=0.01), and AMG from 7 to 10 (n.s.). A rise in baseline S-Crea by more than 25% or 44 μmol/l occurred in 4 and 2 patients in the group with and without AP, respectively. Creatinine increase was reversible in all cases within 7 days. In this study using sensitive methods to detect changes of renal function and tubular toxicity no additional renal function impairment in DSA with angioplasty for RAS compared with DSA alone could be demonstrated. Our data suggest that AP performed for RAS has

Improving accuracy of ET measurement of LISS nozzle to calandria tube clearance

International Nuclear Information System (INIS)

Craig, S.T.; Krause, T.W.; Schankula, J.J.

2006-01-01

The AECL Fuel Channel Inspection System (AFCIS) has been used in an in-reactor field trial to successfully measure the clearance between Liquid Injection Shutdown System (LISS) nozzles and calandria tubes. Each measurement over the full length of a channel added only 15 minutes to the on-channel inspection time. No changes were required to the inspection heads. The only equipment changes made were the addition of a Remote Field Eddy Current (RFEC) module to the eddy current instrument, and minor wiring changes, at the instrument, to achieve a RFEC configuration. With the experience gained from the field trial, factors potentially limiting accuracy were identified. These, and other factors, were investigated and are discussed herein. The RFEC probe is delivered inside the pressure tube. Magnetic fields from the RFEC probe extend through the conducting walls of the pressure tube and calandria tube to interact with the LISS nozzle. Data acquired during the field trial showed the LISS nozzle signal is distinct and the signal-to-noise ratio is very favourable. Nevertheless, comparison of the RFEC measurements to a visual examination, made during the same outage, had the RFEC method underestimating the clearance by 2.5 mm on average. By way of laboratory tests, the following factors were investigated as potential sources of error: resistivity and geometry of LISS nozzle reference/calibration pieces, pressure-tube wall thickness, diameter and resistivity variations, pressure-tube to calandria-tube gap, and radial offsets of the probe within the pressure-tube. The sensitivity to these various noise sources was established. A model, based on fundamental electromagnetic principles, was developed and was used to normalize the effects of LISS nozzle conductivity and geometry. This enabled compensation for various sources of error, and made it possible to produce a correction factor for the field trial data, reducing the average difference from the visual inspection of LISS

Role of ultrasonography in percutaneous renal access in patients with renal anatomic abnormalities.

Science.gov (United States)

Penbegul, Necmettin; Hatipoglu, Namik Kemal; Bodakci, Mehmet Nuri; Atar, Murat; Bozkurt, Yasar; Sancaktutar, Ahmet Ali; Tepeler, Abdulkadir

2013-05-01

To present our experience regarding the feasibility, safety, and efficacy of ultrasound (US)-guided percutaneous nephrolithotomy in anatomically abnormal kidneys. We performed US-guided percutaneous nephrolithotomy in 15 patients with anatomically abnormal kidneys and renal calculi. Of the 15 patients, 5 had horseshoe kidneys, 5 had rotation anomalies, 2 had kyphoscoliosis, and 3 had scoliosis. The stone size, number of access tracts, operative time, hospitalization duration, rate of stone clearance, and complication rate were recorded. Percutaneous access was achieved with US guidance in the operating room by the urologist. Successful renal access was obtained by the surgeon using US guidance in all patients, and a single access was obtained in all cases. Of the 15 patients, 8 were females, and 7 were males; 8 patients had solitary stones, and 7 had multiple calculi. The renal calculi were on the right in 7 patients and on the left in 8. Three patients had previously undergone unsuccessful shock wave lithotripsy. Complete stone clearance was achieved in 13 patients. The mean operative time was 54.2 minutes. No patient required a blood transfusion because of bleeding. Urinary tract infections occurred in 2 patients, who were treated with antibiotics. A double-J catheter was not inserted in any patient; however, a ureteral catheter was used in 3 patients for 1 day. None of the patients had any major complications during the postoperative period. The stone-free rate was 87%, and 2 patients had clinically insignificant residual fragments. Our results have demonstrated that US-guided percutaneous nephrolithotomy can be performed feasibly, safely, and effectively in anatomically abnormal kidneys. Copyright © 2013 Elsevier Inc. All rights reserved.

Comparative study of three methods of estimation of creatinine clearance in critically ill patients.

Science.gov (United States)

Blasco, V; Antonini, F; Zieleskiewicz, L; Hammad, E; Albanèse, J; Martin, C; Leone, M

2014-05-01

At the bedside, the reference method for creatinine clearance determination is based on the measurement of creatinine concentrations in urine and serum (mCrCl). Several models are available to calculate the creatinine clearance from the serum creatinine concentration. This observational survey aimed at testing the hypothesis that the proposed equations are unreliable to determine accurate creatinine clearance in patients admitted to intensive care unit (ICU). Creatinine clearance was determined by the use of mCrCl. Then, we compared three equations: Cockcroft-Gault (CG), Simplified Modification of Diet in Renal Disease (MDRDs), and Chronic Kidney Disease Epidemiology (CKD-EPI) in 156 consecutive patients within the first 24hours after ICU admission. We tested the hypothesis that the three equations were equivalent. The agreement between the three equations was evaluated by linear regression and Bland and Altman analysis. Bland and Altman analysis showed similar agreement between the three equations. The biases and precisions were -4.8±51, -1.3±50, and 8.2±44 for CG, MDRDs, and CKD-EPI equations, respectively (P>0.05). The precisions were similar for the three equations (P>0.05). The percentages of outliers at ±30% were 44%, 45%, and 49% for CG, MDRDs, and CKD-EPI, respectively (P>0.05). Regarding the high percentage of outliers, the use of these equations cannot be recommended in ICU patients. Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

Renal uptake of dimercaptosuccinic acid and glomerular filtration rate in chronic nephropathy at angiotensin converting enzyme inhibition

International Nuclear Information System (INIS)

Kamper, A.L.; Thomsen, H.S.; Nielsen, S.L.; Strandgaard, S.; Herlev Hospital

1990-01-01

Glomerular filtration rate (GFR) and renal uptake of dimercaptosuccinic acid (DMSA) were measured in 31 patients with progressive chronic nephropathy before and immediately after the start of treatment with angiotensin converting enzyme (ACE) inhibitor in order to control adverse effects on kidney function. Scintigrams of the kidneys showed an unaltered distribution of DMSA during treatment. GFR estimated by 51 Cr-EDTA plasma clearance fell by 14% (P 99m Tc-DMSA increased by 10% (P<0.01). It is concluded that DMSA in chronic renal failure is mainly taken up by the tubular cells from the peritubular capillaries since the uptake was unaffected by the acute decrease in GFR. (orig.)

Mechanisms of hypertension in renal radiation

International Nuclear Information System (INIS)

Juncos, L.; Cornejo, J.C.; Cejas, H.; Broglia, C.

1990-01-01

This study was undertaken to investigate the role played by renal functional and structural changes in the development of radiation-induced hypertension. Four groups of rats were studied: (1) left kidney radiated, (2) sham procedure, (3) uninephrectomy followed 3 weeks later by radiation of the contralateral kidney, and (4) uninephrectomy followed by sham procedure 3 weeks later. All radiated rats became hypertensive at 12 weeks (p less than 0.05) and had higher protein excretion (p less than 0.05). In the presence of an intact contralateral kidney, radiation causes mild-to-moderate histological abnormalities, and therefore, creatinine clearance and water and sodium handling do not change. Plasma renin activity increased in this group (p less than 0.05). Radiated uninephrectomized rats showed decreased creatinine clearance (p less than 0.05), but renin activity remained unchanged. These rats developed severe histological abnormalities in glomeruli, interstitia, tubuli, and vessels resulting in increased sodium and water output. The average of individual tubular and interstitial scores correlated significantly with both water intake and output but not with sodium excretion. These studies suggest that in the presence of an intact kidney, renin is an important determinant in the development or maintenance of radiation hypertension, whereas in the absence of the contralateral kidney, severe histological changes and renal failure are prominent despite increased water intake and output. The more severe glomerular sclerosis and proteinuria in the latter model could be related to diminished renal mass

Measurement of renal index on X-CT

International Nuclear Information System (INIS)

Iguchi, Takashi

1991-01-01

Morphological measurements of the kidney were made using X-CT images. Anteroposterior (AP) width of the kidney as well as the renal sinus on both right and left sides and the transverse width of the first lumbar vertebral body were measured from CT images. Changes according to age in AP width of the kidney and the transverse width of the lumbar vertebral body were investigated. As to the ratio of the AP width of the kidney (both right and left) to the transverse width of the lumbar vertebral body, and the ratio of the AP width of the kidney to the AP width of the renal sinus, the changes due to aging and the differences between male and female were studied. The average AP width of the right kidney was 47 mm, while that of the left kidney was 49 mm. The left kidney was slightly larger than the right kidney with statistical significance. In subjects up to 19 years of age, both the AP width of the kidney and the transverse width of the lumbar vertebral body showed correlation with age, while after the age of 20, there was no age-related correlation. The average ratio of the AP width of the kidney to the transverse width of the lumbar vertebral body was 1.13 for the right kidney and 1.19 for the left kidney. The difference between those two items was statistically significant and the changes due to aging were slight. During the age between 4 and 64 years, they were constant and no significant change was noticed. No difference between male and female was found. From the age of 65 years, a decreasing tendency was noticed. The ratios of AP width of the kidney to the AP width of renal sinus for both kidneys in males and females were found to be inversely correlated with age. They were similar to the changes due to aging in renal functions of the cortex system. On CT images, the ratio of AP width could be the index of both the size of the kidney and the thickness of the renal parenchyma respectively. (author)

Use of /sup 99m/Tc diethylenetriaminepentaacetic acid for assessment of renal function in dogs with suspected renal disease

International Nuclear Information System (INIS)

Krawiec, D.R.; Twardock, A.R.; Badertscher, R.R. II; Daniel, G.B.; Dugan, S.J.

1988-01-01

The effectiveness of technetium /sup 99m/-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc DTPA) to assess renal function in 13 dogs with suspected renal disease was evaluated. Glomerular filtration rates (actual GFR) were determined on the basis of endogenous creatinine clearance. Predicted GFR were determined by using /sup 99m/Tc DTPA within 72 hours after the determination of creatinine clearance. The percentage of an IV administered dose of /sup 99m/Tc DTPA in the kidneys (percentage dose) was determined. Two equations were used to calculate predicted GFR, which were derived from previously reported linear regression analysis of inulin (In) and creatinine (Cr) GFR vs percentage dose /sup 99m/Tc DTPA in dog kidneys. The correlations of actual GFR vs predicted GFR (In) and actual GFR vs predicted GFR (Cr) were both r = 0.92. The dogs' mean actual GFR was 1.73 +/- 1.35 ml/min/kg. Their mean predicted GFR (In) and predicted GFR (Cr) were 1.92 +/- 1.42 ml/min/kg and 1.85 +/- 1.27 ml/min/kg, respectively. Therefore, /sup 99m/Tc DTPA can be used with high accuracy as an agent to predict GFR in dogs with suspected renal disease. The procedure for determining GFR by use of nuclear medicine was rapid and noninvasive and appeared to induce little stress in the animals evaluated

Determination of the technetium-99m mercaptoacetyltriglycine plasma clearance in children by means of a single blood sample: a multicentre study

International Nuclear Information System (INIS)

Piepsz, A.; Gordon, I.; Hahn, K.; Kolinska, J.; Kotzerke, J.; Sixt, R.

1993-01-01

A multicentree European study was undertaken in order to determine a reasonable algorithm allowing the determination of overall technetium-99m mercaptoacetyltriglycine clearance using a single blood sample. Employing multiple blood sample clearance as a reference method, it was shown that an acceptable estimation of the MAG3 renal clearance could be obtained using a blood sample taken at any time between 30 and 40 min after tracer injection. After correction for body surface area comparison of clearance determined using (a) the single blood sample and (b) the multiple blood samples provided a coefficient of correlation of 0.949 and an SEE of 27 ml/min. This algorithm is valid for clearance values higher than 100 ml/min/1.73 m 2 and for children older than 1 year of age. (orig.)

Use of nonimaging nuclear medicine techniques to assess the effect of flunixin meglumine on effective renal plasma flow and effective renal blood flow in healthy horses.

Science.gov (United States)

Held, J P; Daniel, G B

1991-10-01

The effect of flunixin meglumine on renal function was studied in 6 healthy horses by use of nonimaging nuclear medicine techniques. Effective renal plasma flow (ERPF) and effective renal blood flow (ERBF) were determined by plasma clearance of 131I-orthoiodohippuric acid before and after administration of flunixin meglumine. Mean ERPF and ERBF was 6.03 ml/min/kg and 10.7 ml/min/kg, respectively, before treatment and was 5.7 ml/min/kg and 9.7 ml/min/kg, respectively, after treatment. Although ERPF and ERBF decreased after flunixin meglumine administration, the difference was not statistically significant.

Techniques for blade tip clearance measurements with capacitive probes

Science.gov (United States)

Steiner, Alexander

2000-07-01

This article presents a proven but advantageous concept for blade tip clearance evaluation in turbomachinery. The system is based on heavy duty probes and a high frequency (HF) and amplifying electronic unit followed by a signal processing unit. Measurements are taken under high temperature and other severe conditions such as ionization. Every single blade can be observed. The signals are digitally filtered and linearized in real time. The electronic set-up is highly integrated. Miniaturized versions of the electronic units exist. The small and robust units can be used in turbo engines in flight. With several probes at different angles in one radial plane further information is available. Shaft eccentricity or blade oscillations can be calculated.

Tc-99m DMSA renal uptake: influence of biochemical and physiologic factors

International Nuclear Information System (INIS)

Yee, C.A.; Lee, H.B.; Blaufox, M.D.

1981-01-01

Thirty-eight female Sprague-Dawley rats were studied to determine the effects of (a) tubular blockade and (b) commonly encountered changes in hydration and acid-base balance, on the urinary excretion and renal localization of Tc-99m dimercaptosuccinic acid (DMSA). Ten additional rats were studied to quantitate the in vivo protein binding of Tc-99m DMSA, and a final group of 12 animals was used to quantitate DMSA distribution in animals with diminished functional renal mass. Both osmotic diuresis and dehydration by water deprivation for 24 hr resulted in a plasma clearance of DMSA slower than in control animals. Acid-base imbalances significantly affected the renal accumulation of DMSA, and acidosis was associated with markedly increased background due to increased liver accumulation. The protein-bound portion of Tc-99m DMSA in the plasma was high, reaching 89% within the first 5 min, and rising very slightly (n.s.) with time. The unbound portion of DMSA had a plasma clearance slightly higher than the GFR. Ablation of large amounts of renal tissue, resulting in significant decreases in GFR, did not significantly affect the renal localization of DMSA in the intact portions of the kidneys. These data demonstrate that commonly encountered changes in acid-base balance and hydration will significantly alter the biologic distribution of Tc-99m DMSA. These factors should be controlled when carrying out clinical studies

Iterative study of renal functions by the continuous perfusion of radioactive tracers before and after the initiation of treatment for diabetes mellitus and hypertension

International Nuclear Information System (INIS)

Mirouze, J.; Monnier, L.; Olivier, C.

1975-01-01

Glomerular filtration and renal plasma flux are measured simultaneously as a result of achieving isotopic equilibrium after the continuous perfusion of 125 I-iothalamate and 131 I-orthoiodohippurate. A good correlation is found between the clearances of 125 I-iothalamate (y) and of inulin or polyfructosan (x): y = 1.18 x + 8.43 (r 0.96; P 131 I-orthoiodohippurate (y') and para-aminohippuric acid (x'): y' = 0.62 x' + 21.2 (r = 0.93; P < 0.001). When the renal function is modified, the iothalamate is not suitable for this technique since the time necessary to reach a radioactive concentration plateau exceeds three hours. Orthoiodohippurate, on the contrary, yields good results. The main advantages of the method in this case are absence of urine collection and rapid achievement of isotopic equilibrium. The repeated study of the renal function of hypertensive patients and of diabetics makes it possible to investigate the effects of anti-hypertension drugs and insulin therapy. Since clonidin improves the clearances slightly, it may be considered for administration in cases of hypertension associated with chronic renal inadequacy. Insulin therapy very rapidly increases the glomerular filtration and renal plasma flux of diabetics by insulin extraction. This improvement depends more on metabolic and haemodynamic changes caused by the insulin than on the correction of disorders affecting the permeability of the basal glomerular membrane

Intraarticular volume and clearance in human synovial effusions

International Nuclear Information System (INIS)

Wallis, W.J.; Simkin, P.A.; Nelp, W.B.; Foster, D.M.

1985-01-01

Intraarticular volumes were measured by radiolabeled albumin (RISA) distribution in chronic knee effusions from 11 rheumatoid arthritis patients and 9 osteoarthritis patients. Volumes of synovial fluid obtained at joint aspiration were substantially less than those found by RISA dilution. Up to 24 hours was needed for full distribution of RISA throughout the intraarticular compartment. Measured 123I and RISA radioactivity over the knee described monoexponential rate constants, lambda (minute-1). The clearance of 123I and RISA from synovial effusions was derived by the formulation volume (ml) X lambda (minute-1) = clearance (ml/minute). RISA clearance in rheumatoid effusions was significantly greater than that found in osteoarthritis effusions. Intraarticular volume and isotope clearance were easily quantified and provide measures for further evaluating the microvascular physiology of synovial effusions

Renal aging in WKY rats: changes in Na+,K+ -ATPase function and oxidative stress.

Science.gov (United States)

Silva, E; Pinto, V; Simão, S; Serrão, M P; Afonso, J; Amaral, J; Pinho, M J; Gomes, P; Soares-da-Silva, P

2010-12-01

It has been suggested that alterations in Na(+),K(+)-ATPase mediate the development of several aging-related pathologies, such as hypertension and diabetes. Thus, we evaluated Na(+),K(+)-ATPase function and H(2)O(2) production in the renal cortex and medulla of Wistar Kyoto (WKY) rats at 13, 52 and 91 weeks of age. Creatinine clearance, proteinuria, urinary excretion of Na(+) and K(+) and fractional excretion of Na(+) were also determined. The results show that at 91 weeks old WKY rats had increased creatinine clearance and did not have proteinuria. Despite aging having had no effect on urinary Na(+) excretion, urinary K(+) excretion was increased and fractional Na(+) excretion was decreased with age. In renal proximal tubules and isolated renal cortical cells, 91 week old rats had decreased Na(+),K(+)-ATPase activity when compared to 13 and 52 week old rats. In renal medulla, 91 week old rats had increased Na(+),K(+)-ATPase activity, paralleled by an increase in protein expression of α(1)-subunit of Na(+),K(+)-ATPase. In addition, renal H(2)O(2) production increased with age and at 91 weeks of age renal medulla H(2)O(2) production was significantly higher than renal cortex production. The present work demonstrates that although at 91 weeks of age WKY rats were able to maintain Na(+) homeostasis, aging was accompanied by alterations in renal Na(+),K(+)-ATPase function. The observed increase in oxidative stress may account, in part, for the observed changes. Possibly, altered Na(+),K(+)-ATPase renal function may precede the development of age-related pathologies and loss of renal function. Copyright © 2010 Elsevier Inc. All rights reserved.

Cerebrospinal fluid clearance in Alzheimer disease measured with dynamic PET

DEFF Research Database (Denmark)

De Leon, Mony J.; Li, Yi; Okamura, Nobuyuki

2017-01-01

Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing the cribrif......Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer disease (AD) comes primarily from rodent models. However, unlike rodents, in which predominant extracranial CSF egress is via olfactory nerves traversing...

Assessment of 99mTc-DMSA renoscintigraphy and uptake compared with creatinine clearance in rats with drug-induced nephrotoxicity, 1

International Nuclear Information System (INIS)

Yamada, Masafumi

1991-01-01

For evaluation of technetium-99m dimercaptosuccinic acid ( 99m Tc-DMSA) renal uptake as an absolute renal function, 99m Tc-DMSA uptake was compared with endogenous creatinine clearance (Ccr) in gentamicin-induced nephrotoxicity. Gentamicin (40 mg/kg/day) was given subcutaneously to male Wistar rats for periods of 3, 6, 9 and 12 days. On the next day, the renoscintigraphy was performed 2 hours following intravenous injection of 99m Tc-DMSA and Ccr was measured. On the 7th day, 99m Tc-DMSA uptake was significantly lower in the treated rats than that in control (32.27±0.92 vs 39.84±2.24%; p 99m Tc-DMSA uptake was measured and the histological examination was done. On the 4th day, 99m Tc-DMSA uptake was significantly lower than that on the 1st day (32.32±3.00 vs 38.91±1.95%; p 99m Tc-DMSA uptake reduces earlier than Ccr in gentamicin-induced nephrotoxicity and 99m Tc-DMSA uptake is a reliable indicator in the evaluation of a renal function in drug-induced nephrotoxicity. (author)

Assessment of glomerular filtration rate measurement with plasma sampling: a technical review.

Science.gov (United States)

Murray, Anthony W; Barnfield, Mark C; Waller, Michael L; Telford, Tania; Peters, A Michael

2013-06-01

This article reviews available radionuclide-based techniques for glomerular filtration rate (GFR) measurement, focusing on clinical indications for GFR measurement, ideal GFR radiopharmaceutical tracer properties, and the 2 most common tracers in clinical use. Methods for full, 1-compartment, and single-sample renal clearance characterization are discussed. GFR normalization and the role of GFR measurement in chemotherapy dosing are also considered.

Oral Bicarbonate Slows Decline of Residual Renal Function in Peritoneal Dialysis Patients.

Science.gov (United States)

Liu, Xiang-Yang; Gao, Xiu-Mei; Zhang, Ning; Chen, Rui; Wu, Feng; Tao, Xin-Chao; Li, Chun-Jun; Zhang, Ping; Yu, Pei

2017-01-01

Metabolic acidosis is a common consequence of end-stage renal disease (ESRD) which may result in a substantial adverse outcome. The effect of oral bicarbonate on the preservation of residual renal function (RRF) in peritoneal dialysis (PD) patients has been rarely reported. We randomly assigned 40 continuous ambulatory peritoneal dialysis (CAPD) patients to the oral bicarbonate group or placebo group at a 1: 1 ratio. All enrollments were followed for a duration of 104 weeks. We took residual creatinine clearance (CCr), a measure of residual renal function (RRF), as the primary outcome. Residual CCr was calculated as the average of urea and creatinine clearance from a 24-hour urine collection. Thirteen patients in the placebo group and 15 patients in the treatment group completed the 104 weeks of follow-up with a comparable dropout rate (placebo group: 35% vs treatment group: 25%). Compared with the placebo group, serum bicarbonate in treatment group was significantly increased at each time point, and oral bicarbonate resulted in a slower declining rate of residual CCr (F=5.113, p=0.031). Baseline residual CCr at enrollment also had a significant effect on residual CCr (F=168.779, Pcalculate a comorbidity score had no significant effect on residual CCr loss (F=0.168, P=0.685). Oral bicarbonate may have a RRF preserving effect in CAPD patients, and a normal to high level of serum bicarbonate (≥24mmol/L) may be appropriate for RRF preservation. © 2017 The Author(s). Published by S. Karger AG, Basel.

Targeted reduction of advanced glycation improves renal function in obesity

DEFF Research Database (Denmark)

Harcourt, Brooke E; Sourris, Karly C; Coughlan, Melinda T

2011-01-01

-lowering pharmaceutical, alagebrium, and mice in which the receptor for AGE (RAGE) was deleted. Obesity, resulting from a diet high in both fat and AGE, caused renal impairment; however, treatment of the RAGE knockout mice with alagebrium improved urinary albumin excretion, creatinine clearance, the inflammatory profile...... if treatments that lower tissue AGE burden in patients and mice would improve obesity-related renal dysfunction. Overweight and obese individuals (body mass index (BMI) 26-39¿kg/m(2)) were recruited to a randomized, crossover clinical trial involving 2 weeks each on a low- and a high-AGE-containing diet. Renal......, and renal oxidative stress. Alagebrium treatment, however, resulted in decreased weight gain and improved glycemic control compared with wild-type mice on a high-fat Western diet. Thus, targeted reduction of the advanced glycation pathway improved renal function in obesity....

Transcutaneous measurement of glomerular filtration rate in small rodents: through the skin for the win?

Science.gov (United States)

Ellery, Stacey J; Cai, Xiaochu; Walker, David D; Dickinson, Hayley; Kett, Michelle M

2015-03-01

Rodent models of renal physiology and pathology are crucial to our understanding of the molecular, histological and functional sequelae that contribute to kidney diseases. One of the most important measures of renal function is glomerular filtration rate (GFR). While the accurate determination of GFR is pivotal to understanding the progression of disease and/or the benefits of treatment strategies, in rodents the conventional methods for assessment of GFR are inconvenient and cumbersome, not the least because they involve stress and often anaesthesia. The legitimacy of assay-based assessment of plasma and urine markers of GFR in mice has also been heavily scrutinized for their insensitivity to minor declines in GFR and inaccurate detection of renal biomarkers. While infusion-based clearance methods of GFR assessment are thus the gold standard in terms of accuracy, they are limited by the fact that they are primarily non-recovery procedures. This presents a dilemma when trying to document the progression of renal disease, as these measures cannot be taken in the same experimental subject. Here we review a technique of transcutaneous measurement of fluorescein isothiocyanate-labelled sinistrin to calculate GFR in small rodents, using a non-invasive clearance device (NIC-Kidney Device). This is a recently validated non-invasive technique for measuring GFR in small rodents that allows for the real-time measurement of GFR in conscious animals, without the need for plasma and urine assays. © 2014 Asian Pacific Society of Nephrology.

The outcome of extracorporeal shockwave lithotripsy for renal pelvic stone with and without JJ stent--a comparative study.

Science.gov (United States)

Mohayuddin, Nazim; Malik, Hamad Afzal; Hussain, Manzoor; Tipu, Salman Ahmed; Shehzad, Asad; Hashmi, Altaf; Naqvi, Syed Ali Anwar; Rizvi, Syed Adibul Hasan

2009-03-01

To compare the outcome of Extra corporeal shockwave lithotripsy for a renal pelvic stone with and without JJ stent. A comparative cross sectional study was carried out at Sindh Institute of Urology and Transplantation from January 2007 to January 2008. Eighty patients with renal pelvic stone measuring 2cm +/- 2mm were selected for treatment with Extra Corporeal Shockwave Lithotripsy (ESWL). All of these patients were adults with normal renal function and had unilateral renal stones with negative urine cultures. Patients with renal failure and children were excluded. They were divided into two groups of 40 each. Group A patients underwent ESWL without a JJ stent and in Group B a JJ stent was placed before ESWL. SLX F2 electromagnetic ESWL machine was used to impart shock waves. 3000 shockwaves were given in a session. Both the groups were compared for renal colic, steinstrasse, fever, lower urinary tract symptoms (LUTS) emergency room visits and hospital admissions, stone clearance, number of ESWL sessions, auxilliary procedures, (percutaneous nephrostomy or ureterorenoscopy) and cost. Ureteric colic occurred in 13 (32.5%) patients in group A and in 3 (7.5%) patient in group B. Steinstrasse developed in 4 (10%) patients with out JJ stent and in 3 (7.5%) patients with JJ stent. Fever was encountered in 1 (2.5%) patient in group A and in 3 (7.5%) patient in group B. Mean emergency room visits were 2.1 per patient in group A and 0.7 per patient in group B. Stone clearance occurred in 33 (82.5%) patients in group A and 31 (77.5%) in group B. In group B lower urinary tract symptoms were found in 50% versus 20% in group A. Auxillary procedure was performed in one (2.5%) patient each in both groups. Pre ESWL JJ stenting for a 2 cm +/- 2 mm renal stone was not beneficial in terms of steinstrasse, fever, stone clearance and number of ESWL sessions. However ureteric colic was significantly less in the stented group. Lower urinary tract symptoms (LUTS) was also significantly

Methotrexate Associated Renal Impairment Is Related to Delayed Elimination of High-Dose Methotrexate

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Shi-Long Yang

2015-01-01

Full Text Available Although Methotrexate (MTX is an effective drug for the treatment of acute lymphoblastic leukemia (ALL, the toxicity remains a significant problem. In this prospective study, fifty-four patients with ALL were enrolled. 3 g or 5 g MTX/m2 was administered over 24 hours. Serum MTX concentrations were determined in 24, 48, and 96 hours after MTX infusion. Serum creatinine concentrations and creatinine clearance rate (CCR were determined before and 24 and 48 hours after MTX infusion. A total of 173 courses of MTX infusion were administered. The serum creatinine concentrations did not change much after MTX infusion while the CCR was gradually decreased. MTX clearance status was independently related to CCR decrease, with the risk of 8.07 to develop renal impairment in patients with delayed MTX elimination. Serum creatinine concentration, serum creatinine ratio, CCR, and CCR ratio at 24 hours were all related to MTX elimination delay. Patients with serum creatinine level >35.0 μmol/L, creatinine ratio >1.129, or CCR <100.0 mL/min were more likely to undergo MTX elimination delay. In conclusion, MTX could induce transient renal impairment and compromised renal function will delay MTX clearance. The serum creatinine concentration and the ratio and CCR are useful tools for evaluating MTX elimination status.

Effect of a keto acid-amino acid supplement on the metabolism and renal elimination of branched-chain amino acids in patients with chronic renal insufficiency on a low protein diet.

Science.gov (United States)

Teplan, V; Schück, O; Horácková, M; Skibová, J; Holecek, M

2000-10-27

The aim of our study was to evaluate the effect of a low-protein diet supplemented with keto acids-amino acids on renal function and urinary excretion of branched-chain amino acids (BCAA) in patients with chronic renal insufficiency (CRI). In a prospective investigation 28 patients with CRI (16 male, 12 female, aged 28-66 yrs, CCr 18.6 +/- 10.2 ml/min) on a low-protein diet (0.6 g of protein /kg BW/day and energy intake 140 kJ/kg BW/day) for a period of one month were included. Subsequently, this low protein diet was supplemented with keto acids-amino acids at a dose of 0.1 g/kg BW/day orally for a period of 3 months. Examinations performed at baseline and at the end of the follow-up period revealed significant increase in the serum levels of BCAA leucine (p Keto acid-amino acid administration had no effect on renal function and on the clearance of inulin, para-aminohippuric acid. Endogenous creatinine and urea clearance remained unaltered. A significant correlation between fractional excretion of sodium and leucine (p diet the supplementation of keto acids-amino acids does not affect renal hemodynamics, but is associated--despite increases in plasma concentrations--with a reduction of renal amino acid and protein excretion suggesting induction of alterations in the tubular transport mechanisms.

Renal Atrophy Secondary to Chemoradiotherapy of Abdominal Malignancies

International Nuclear Information System (INIS)

Yang, Gary Y.; May, Kilian Salerno; Iyer, Renuka V.; Chandrasekhar, Rameela M.A.; Wilding, Gregory E.; McCloskey, Susan A.; Khushalani, Nikhil I.; Yendamuri, Saikrishna S.; Gibbs, John F.; Fakih, Marwan; Thomas, Charles R.

2010-01-01

Purpose: To identify factors predictive of renal atrophy after chemoradiotherapy of gastrointestinal malignancies. Methods and Materials: Patients who received chemotherapy and abdominal radiotherapy (RT) between 2002 and 2008 were identified for this study evaluating change in kidney size and function after RT. Imaging and biochemical data were obtained before and after RT in 6-month intervals. Kidney size was defined by craniocaudal measurement on CT images. The primarily irradiated kidney (PK) was defined as the kidney that received the greater mean kidney dose. Receiver operating characteristic (ROC) curves were generated to predict risk for renal atrophy. Results: Of 130 patients, median age was 64 years, and 51.5% were male. Most primary disease sites were pancreas and periampullary tumors (77.7%). Median follow-up was 9.4 months. Creatinine clearance declined 20.89%, and size of the PK decreased 4.67% 1 year after completion of chemoradiation. Compensatory hypertrophy of the non-PK was not seen. Percentage volumes of the PK receiving ≥10 Gy (V 10 ), 15 Gy (V 15 ), and 20 Gy (V 20 ) were significantly associated with renal atrophy 1 year after RT (p = 0.0030, 0.0029, and 0.0028, respectively). Areas under the ROC curves for V 10 , V 15 , and V 20 to predict >5% decrease in PK size were 0.760, 0.760, and 0.762, respectively. Conclusions: Significant detriments in PK size and renal function were seen after abdominal RT. The V 10 , V 15 , and V 20 were predictive of risk for PK atrophy 1 year after RT. Analyses suggest the association of lower-dose renal irradiation with subsequent development of renal atrophy.