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Find video protocols related to scientific articles indexed in Pubmed.
Nephron Hypertrophy and Glomerulosclerosis and Their Association with Kidney Function and Risk Factors among Living Kidney Donors.
Clin J Am Soc Nephrol
PUBLISHED: 10-15-2014
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The relationship of kidney function and CKD risk factors to structural changes in the renal parenchyma of normal adults is unclear. This study assessed whether nephron hypertrophy and nephrosclerosis had similar or different associations with kidney function and risk factors.
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Stone Composition as a Function of Age and Sex.
Clin J Am Soc Nephrol
PUBLISHED: 10-04-2014
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Kidney stones are heterogeneous but often grouped together. The potential effects of patient demographics and calendar month (season) on stone composition are not widely appreciated.
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The ROKS Nomogram for Predicting a Second Symptomatic Stone Episode.
J. Am. Soc. Nephrol.
PUBLISHED: 08-07-2014
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Most patients with first-time kidney stones undergo limited evaluations, and few receive preventive therapy. A prediction tool for the risk of a second kidney stone episode is needed to optimize treatment strategies. We identified adult first-time symptomatic stone formers residing in Olmsted County, Minnesota, from 1984 to 2003 and manually reviewed their linked comprehensive medical records through the Rochester Epidemiology Project. Clinical characteristics in the medical record before or up to 90 days after the first stone episode were evaluated as predictors for symptomatic recurrence. A nomogram was developed from a multivariable model based on these characteristics. There were 2239 first-time adult kidney stone formers with evidence of a passed, obstructing, or infected stone causing pain or gross hematuria. Symptomatic recurrence occurred in 707 of these stone formers through 2012 (recurrence rates at 2, 5, 10, and 15 years were 11%, 20%, 31%, and 39%, respectively). A parsimonious model had the following risk factors for recurrence: younger age, male sex, white race, family history of stones, prior asymptomatic stone on imaging, prior suspected stone episode, gross hematuria, nonobstructing (asymptomatic) stone on imaging, symptomatic renal pelvic or lower-pole stone on imaging, no ureterovesicular junction stone on imaging, and uric acid stone composition. Ten-year recurrence rates varied from 12% to 56% between the first and fifth quintiles of nomogram score. The Recurrence of Kidney Stone nomogram identifies kidney stone formers at greatest risk for a second symptomatic episode. Such individuals may benefit from medical intervention and be good candidates for prevention trials.
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Distinguishing Characteristics of Idiopathic Calcium Oxalate Kidney Stone Formers with Low Amounts of Randall's Plaque.
Clin J Am Soc Nephrol
PUBLISHED: 08-04-2014
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Overgrowth of calcium oxalate on Randall's plaque is a mechanism of stone formation among idiopathic calcium oxalate stone-formers (ICSFs). It is less clear how stones form when there is little or no plaque.
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Thiazide Diuretic Prophylaxis for Kidney Stones and the Risk of Diabetes Mellitus.
J. Urol.
PUBLISHED: 06-24-2014
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Thiazide diuretics used to treat hypertension are associated with a modest risk of diabetes mellitus. It is unknown if there is a similar risk with kidney stone prevention.
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Kidney stones are common after bariatric surgery.
Kidney Int.
PUBLISHED: 06-04-2014
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Obesity, a risk factor for kidney stones and chronic kidney disease (CKD), is effectively treated with bariatric surgery. However, it is unclear whether surgery alters stone or CKD risk. To determine this we studied 762 Olmsted County, Minnesota residents who underwent bariatric surgery and matched them with equally obese control individuals who did not undergo surgery. The majority of bariatric patients underwent standard Roux-en-Y gastric bypass (RYGB; 78%), with the remainder having more malabsorptive procedures (very long limb RYGB or biliopancreatic diversion/duodenal switch; 14%) or restrictive procedures (laparoscopic banding or sleeve gastrectomy; 7%). The mean age was 45 years with 80% being female. The mean preoperative body mass index (BMI) was 46.7?kg/m(2) for both cohorts. Rates of kidney stones were similar between surgery patients and controls at baseline, but new stone formation significantly increased in surgery patients (11.0%) compared with controls (4.3%) during 6.0 years of follow-up. After malabsorptive and standard surgery, the comorbidity-adjusted hazard ratio of incident stones was significantly increased to 4.15 and 2.13, respectively, but was not significantly changed for restrictive surgery. The risk of CKD significantly increased after the malabsorptive procedures (adjusted hazard ratio of 1.96). Thus, while RYGB and malabsorptive procedures are more effective for weight loss, both are associated with increased risk of stones, while malabsorptive procedures also increase CKD risk.Kidney International advance online publication, 29 October 2014; doi:10.1038/ki.2014.352.
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Use of metformin in diseases of aging.
Curr. Diab. Rep.
PUBLISHED: 04-23-2014
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Metformin is the most commonly prescribed medication for type 2 diabetes (T2DM) in the world. It has primacy in the treatment of this disease because of its safety record and also because of evidence for reduction in the risk of cardiovascular events. Evidence has accumulated indicating that metformin is safe in people with stage 3 chronic kidney disease (CKD-3). It is estimated that roughly one-quarter of people with CKD-3 and T2DM in the United States (well over 1 million) are ineligible for metformin treatment because of elevated serum creatinine levels. This could be overcome if a scheme, perhaps based on pharmacokinetic studies, could be developed to prescribe reduced doses of metformin in these individuals. There is also substantial evidence from epidemiologic studies to indicate that metformin may not only be safe, but may actually benefit people with heart failure (HF). Prospective, randomized trials of the use of metformin in HF are needed to investigate this possibility.
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Automated assessment of renal cortical surface roughness from computerized tomography images and its association with age.
Acad Radiol
PUBLISHED: 03-26-2014
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Nephrosclerosis occurs with aging and is characterized by increased kidney subcapsular surface irregularities at autopsy. Assessments of cortical roughness in vivo could provide an important measure of nephrosclerosis. The purpose of this study was to develop and validate an image-processing algorithm for quantifying renal cortical surface roughness in vivo and determine its association with age.
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Chronic kidney disease and associated mortality after liver transplantation--a time-dependent analysis using measured glomerular filtration rate.
J. Hepatol.
PUBLISHED: 02-25-2014
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The accuracy of creatinine-based estimated GFR (eGFR) in assessing the prevalence of chronic kidney disease (CKD) and associated mortality after liver transplantation (LTx) is unknown. Using measured GFR (mGFR) by iothalamate clearance, we determined the prevalence of the entire spectrum of renal dysfunction and the impact of CKD on mortality after LTx.
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Serum cystatin C predicts vancomycin trough levels better than serum creatinine in hospitalized patients: a cohort study.
Crit Care
PUBLISHED: 02-04-2014
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Serum cystatin C can improve glomerular filtration rate (GFR) estimation over creatinine alone, but whether this translates into clinically relevant improvements in drug dosing is unclear.
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Performance of creatinine-based GFR estimating equations in solid-organ transplant recipients.
Am. J. Kidney Dis.
PUBLISHED: 01-28-2014
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Accurate assessment of kidney function is important for the management of solid-organ transplant recipients. In other clinical populations, glomerular filtration rate (GFR) most commonly is estimated using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine or the 4-variable MDRD (Modification of Diet in Renal Disease) Study equation. The accuracy of these equations compared with other GFR estimating equations in transplant recipients has not been carefully studied.
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Increased circulating inflammatory endothelial cells in blacks with essential hypertension.
Hypertension
PUBLISHED: 06-24-2013
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Morbidity and mortality attributable to hypertension are higher in black essential hypertensive (EH) compared with white EH patients, possibly related to differential effects on vascular injury and repair. Although circulating endothelial progenitor cells (EPCs) preserve endothelial integrity, inflammatory endothelial cells (IECs) detach from sites of injury and represent markers of vascular damage. We hypothesized that blood levels of IECs and inflammatory markers would be higher in black EH compared with white EH patients. Inferior vena cava and renal vein levels of CD34+/KDR+ (EPC) and VAP-1+ (IEC) cells were measured by fluorescence-activated cell sorting in white EH and black EH patients under fixed sodium intake and blockade of the renin-angiotensin system, and compared with systemic levels in normotensive control subjects (n=19 each). Renal vein and inferior vena cava levels of inflammatory cytokines and EPC homing factors were measured by Luminex. Blood pressure, serum creatinine, lipids, and antihypertensive medications did not differ between white and black EH patients, and EPC levels were decreased in both. Circulating IEC levels were elevated in black EH patients, and inversely correlated with EPC levels (R(2)=0.58; P=0.0001). Systemic levels of inflammatory cytokines and EPC homing factors were higher in black EH compared with white EH patients, and correlated directly with IECs. Renal vein inflammatory cytokines, EPCs, and IECs did not differ from their circulating levels. Most IECs expressed endothelial markers, fewer expressed progenitor cell markers, but none showed lymphocyte or phagocytic cell markers. Thus, increased release of cytokines and IECs in black EH patients may impair EPC reparative capacity and aggravate vascular damage, and accelerate hypertension-related complications.
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Nephrolithiasis and loss of kidney function.
Curr. Opin. Nephrol. Hypertens.
PUBLISHED: 06-06-2013
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The prevalence of nephrolithiasis has been on the rise over recent decades. There have also been extensive efforts to identify risk factors for chronic kidney disease (CKD). The purpose of this review is to highlight recent evidence on the association of nephrolithiasis with the development of CKD and end-stage renal disease (ESRD).
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Urine but not serum soluble urokinase receptor (suPAR) may identify cases of recurrent FSGS in kidney transplant candidates.
Transplantation
PUBLISHED: 06-06-2013
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Recently, serum soluble urokinase receptor (suPAR) has been proposed as a cause of two thirds of cases of focal segmental glomerulosclerosis (FSGS). It was noted to be uniquely elevated in cases of primary FSGS, with higher levels noted in cases that recurred after transplantation. It is also suggested as a possible target and marker of therapy.
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GFR estimating equations: getting closer to the truth?
Clin J Am Soc Nephrol
PUBLISHED: 05-23-2013
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The application of serum creatinine and cystatin C in patients with CKD has been limited to using estimated glomerular filtration rate (eGFR). Criteria for choosing the best GFR estimating equation are 1) accuracy in estimating measured GFR, 2) optimal discrimination of clinical outcomes, and 3) association with CKD risk factors and outcomes similar to that of measured GFR. Notably, these criteria are often not in agreement; and while the last criterion is the most important, it has been widely overlooked. The primary problem with eGFR is that the non-GFR determinants of serum creatinine and cystatin C, as well as their surrogates (age, sex, and race), associate with CKD risk factors and outcomes. This leads to a distorted understanding of CKD, though eGFR based on serum creatinine appears to be less biased than eGFR based on cystatin C. Because of this problem, the use of eGFR should be limited to settings where knowing actual GFR is relevant and eGFR is more informative about GFR than serum creatinine or cystatin C alone. Such settings include staging CKD severity by GFR and dosing medications cleared by glomerular filtration. Alternatively, the diagnosis of CKD, the longitudinal progression of CKD, and prognostic models for CKD are settings where serum creatinine and cystatin C can be better applied and interpreted without eGFR.
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MDRD versus CKD-EPI equation to estimate glomerular filtration rate in kidney transplant recipients.
Transplantation
PUBLISHED: 03-21-2013
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The new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine-based equation was developed to address the systematic underestimation of the glomerular filtration rate (GFR) by the Modification of Diet in Renal Disease (MDRD) Study equation in patients with a relatively well-preserved kidney function. The performance of the new equation for kidney transplant recipients is discussed.
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Age, kidney function, and risk factors associate differently with cortical and medullary volumes of the kidney.
Kidney Int.
PUBLISHED: 03-20-2013
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The kidney atrophies in patients with advanced chronic kidney disease (CKD) but factors influencing kidney size in normal adults are less clear. To help define this, we measured kidney volumes on contrast-enhanced computed tomographic images from 1344 potential kidney donors (aged 18-75 years). Cortical volume per body surface area progressively declined in both genders with increased age. Statistically, this was primarily dependent on the age-related decline in glomerular filtration rate (GFR). Independent predictors of increased cortical volume per body surface area were male gender, increased GFR, increased 24-h urine albumin, current smoker, and decreased high-density lipid cholesterol. Medullary volume per body surface area increased with age in men, while it increased with age in women until the age of 50 years followed by a subsequent decline. Independent predictors of increased medullary volume per body surface area were older age, male gender, increased GFR, increased 24-h urine albumin, increased serum glucose, and decreased serum uric acid. Thus, while cortical volume declines with age along the same biological pathway as the age-related decline in GFR, albuminuria and some risk factors are actually associated with increased cortical or medullary volume among relatively healthy adults. Underlying hypertrophy or atrophy of different nephron regions may explain these findings.Kidney International advance online publication, 25 September 2013; doi:10.1038/ki.2013.359.
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Phenotypic characterization of kidney stone formers by endoscopic and histological quantification of intrarenal calcification.
Kidney Int.
PUBLISHED: 03-02-2013
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Interstitial Randalls plaques and collecting duct plugs are distinct forms of renal calcification thought to provide sites for stone retention within the kidney. Here we assessed kidney stone precursor lesions in a random cohort of stone formers undergoing percutaneous nephrolithotomy. Each accessible papilla was endoscopically mapped following stone removal. The percent papillary surface area covered by plaque and plug were digitally measured using image analysis software. Stone composition was determined by micro-computed tomography and infrared analysis. A representative papillary tip was biopsied. The 24-h urine collections were used to measure supersaturation and crystal growth inhibition. The vast majority (99%) of stone formers had Randalls plaque on at least 1 papilla, while significant tubular plugging (over 1% of surface area) was present in about one-fifth of patients. Among calcium oxalate stone formers the amount of Randalls plaque correlated with higher urinary citrate levels. Tubular plugging correlated positively with pH and brushite supersaturation but negatively with citrate excretion. Lower urinary crystal growth inhibition predicted the presence of tubular plugging but not plaque. Thus, tubular plugging may be more common than previously recognized among patients with all types of stones, including some with idiopathic calcium oxalate stones.
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Estimating the glomerular filtration rate from serum creatinine is better than from cystatin C for evaluating risk factors associated with chronic kidney disease.
Kidney Int.
PUBLISHED: 02-20-2013
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Chronic kidney disease risk factors may associate with the estimated glomerular filtration rate (eGFR) differently than with the measured GFR. To examine this, we evaluated 1150 patients (mean age 65 years) in two community cohorts for risk factors, measured GFR by iothalamate clearance, and eGFR based on creatinine (Cr), cystatin C (CysC), or both. The interaction between each risk factor and eGFR (relative to measured GFR) identified risk factor associations with eGFR along non-GFR pathways. In a subset of 40 patients with two visits, the mean coefficient of variation was 8.2% for measured GFR, 6.4% for eGFRCr, 8.2% for eGFRCr-CysC, and 10.7% for eGFRCysC. The measured GFR was better correlated with eGFRCr-CysC (r, 0.74) than eGFRCr (r, 0.70) or eGFRCysC (r, 0.68). Lower measured GFR associated with lower 24-hour urine creatinine, albuminuria, hypertension, diabetes, higher triglycerides, and higher uric acid. Lower eGFRCr had these same associations except for an association with higher 24-hour urine creatinine along a non-GFR pathway. Lower eGFRCysC and eGFRCr-CysC also had these same associations but also associated with obesity, albuminuria, hypertension, diabetes, higher triglycerides, higher C-reactive protein, and higher uric acid along non-GFR pathways. Thus, cystatin C improves estimation of GFR over creatinine alone; however, the association between most of the risk factors and GFR was more accurate by eGFR based on creatinine alone. This is explained by the association of these risk factors with the non-GFR determinants of cystatin C.
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Measurement of urinary TGF-?1 in patients with diabetes mellitus and normal controls.
Clin. Biochem.
PUBLISHED: 02-14-2013
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Increasing evidence links TGF-?1 to progression of renal fibrosis including its association with diabetic nephropathy (DN). Current ELISA assays are not sensitive enough to measure TGF-?1 in the urine of many clinically healthy individuals, even those with established renal disease. The objective of this study was to validate a sensitive urinary assay for TGF-?1 and compare levels between healthy controls and patients with established DN.
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Current computed tomography techniques can detect duct of Bellini plugging but not Randalls plaques.
Urology
PUBLISHED: 02-12-2013
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To assess the ability of noninvasive computed tomography (CT) scans to detect interstitial calcium phosphate deposits (Randalls plaques) and duct of Bellini plugs, which are possible stone precursor lesions.
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Urinary C-type natriuretic peptide excretion: a potential novel biomarker for renal fibrosis during aging.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 08-24-2011
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Renal aging is characterized by structural changes in the kidney including fibrosis, which contributes to the increased risk of kidney and cardiac failure in the elderly. Studies involving healthy kidney donors demonstrated subclinical age-related nephropathy on renal biopsy that was not detected by standard diagnostic tests. Thus there is a high-priority need for novel noninvasive biomarkers to detect the presence of preclinical age-associated renal structural and functional changes. C-type natriuretic peptide (CNP) possesses renoprotective properties and is present in the kidney; however, its modulation during aging remains undefined. We assessed circulating and urinary CNP in a Fischer rat model of experimental aging and also determined renal structural and functional adaptations to the aging process. Histological and electron microscopic analysis demonstrated significant renal fibrosis, glomerular basement membrane thickening, and mesangial matrix expansion with aging. While plasma CNP levels progressively declined with aging, urinary CNP excretion increased, along with the ratio of urinary to plasma CNP, which preceded significant elevations in proteinuria and blood pressure. Also, CNP immunoreactivity was increased in the distal and proximal tubules in both the aging rat and aging human kidneys. Our findings provide evidence that urinary CNP and its ratio to plasma CNP may represent a novel biomarker for early age-mediated renal structural alterations, particularly fibrosis. Thus urinary CNP could potentially aid in identifying subjects with preclinical structural changes before the onset of symptoms and disease, allowing for the initiation of strategies designed to prevent the progression of chronic kidney disease particularly in the aging population.
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Senile nephrosclerosis--does it explain the decline in glomerular filtration rate with aging?
Nephron Physiol
PUBLISHED: 08-10-2011
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Nephrosclerosis can be defined by the presence of glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arteriosclerosis on renal biopsy. Chronic kidney disease is identified clinically by a reduction in glomerular filtration rate (GFR) and has been characterized histologically by nephrosclerosis. Many relatively healthy older adults have been diagnosed with chronic kidney disease because of a decline in GFR with normal aging. Recent data show that in healthy adults (living kidney donors), nephrosclerosis on renal biopsy does not associate with GFR independent of age. This may be explained by the decline in GFR and nephrosclerosis being universal with aging (i.e. senescence), by structural changes in the kidney other than nephrosclerosis impacting GFR, or by extrarenal factors affecting GFR decline with age. However, the argument that the age-related decline in GFR can be fully explained by the development of nephrosclerosis in a subset of older adults is not supported by existing data.
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The impact of interlaboratory differences in cystatin C assay measurement on glomerular filtration rate estimation.
Clin J Am Soc Nephrol
PUBLISHED: 07-28-2011
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Cystatin C (CysC) is a promising marker of GFR. Several equations have been derived to estimate GFR from its serum concentration. Heterogeneity in the performance of these equations exists in validation studies even when the same CysC assay from the same manufacturer is utilized. This study was designed to examine the differences in CysC and GFR estimation (eGFR) using Siemens nephelometric immunoassay and the Mayo Clinic equation. The ability of the eGFRs to predict measured GFR was also examined.
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Chronic kidney disease in kidney stone formers.
Clin J Am Soc Nephrol
PUBLISHED: 07-22-2011
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Recent population studies have found symptomatic kidney stone formers to be at increased risk for chronic kidney disease (CKD). Although kidney stones are not commonly identified as the primary cause of ESRD, they still may be important contributing factors. Paradoxically, CKD can be protective against forming kidney stones because of the substantial reduction in urine calcium excretion. Among stone formers, those with rare hereditary diseases (cystinuria, primary hyperoxaluria, Dent disease, and 2,8 dihydroxyadenine stones), recurrent urinary tract infections, struvite stones, hypertension, and diabetes seem to be at highest risk for CKD. The primary mechanism for CKD from kidney stones is usually attributed to an obstructive uropathy or pyelonephritis, but crystal plugs at the ducts of Bellini and parenchymal injury from shockwave lithotripsy may also contribute. The historical shift to less invasive surgical management of kidney stones has likely had a beneficial impact on the risk for CKD. Among potential kidney donors, past symptomatic kidney stones but not radiographic stones found on computed tomography scans were associated with albuminuria. Kidney stones detected by ultrasound screening have also been associated with CKD in the general population. Further studies that better classify CKD, better characterize stone formers, more thoroughly address potential confounding by comorbidities, and have active instead of passive follow-up to avoid detection bias are needed.
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Relative performance of the MDRD and CKD-EPI equations for estimating glomerular filtration rate among patients with varied clinical presentations.
Clin J Am Soc Nephrol
PUBLISHED: 07-07-2011
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The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was developed using both CKD and non-CKD patients to potentially replace the Modification of Diet in Renal Disease (MDRD) equation that was derived with only CKD patients. The objective of our study was to compare the accuracy of the MDRD and CKD-EPI equations for estimating GFR in a large group of patients having GFR measurements for diverse clinical indications.
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Risk factor profile for chronic kidney disease is similar to risk factor profile for small artery disease.
J. Hypertens.
PUBLISHED: 07-02-2011
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We investigated whether chronic kidney disease detected by increased serum creatinine (S(Cr)) or urine albumin-to-creatinine ratio (U(ACR)) may reflect arteriosclerosis involving the kidneys. The sample consisted of 1585 members of sibships (804 non-Hispanic whites and 781 non-Hispanic blacks) in which at least two siblings had primary hypertension. We first evaluated the correlations of increased S(Cr) and U(ACR) with the presence of cerebral small vessel arteriosclerosis, which was determined by increased subcortical white matter hyperintensity (WMH) volume on brain magnetic resonance imaging; and with peripheral large vessel arteriosclerosis, which was determined by decreased ankle-brachial index (ABI). After age adjustment, increased S(Cr) and U(ACR) correlated with increased WMH volume (0.54 and 0.52, respectively) and with decreased ABI (0.50 and 0.54, respectively; all P < 0.001). We then used logistic regression to evaluate the dependency of each measure of disease on conventional risk factors for arteriosclerosis to assess whether the risk factors effects were proportional across different measures of disease.
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Shock wave lithotripsy and diabetes mellitus: a population-based cohort study.
Urology
PUBLISHED: 05-12-2011
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To determine if shock wave lithotripsy (SWL) is associated with diabetes mellitus (DM) in a community setting. The pancreas is vulnerable to injury at SWL as evidenced by case studies; thus, concern exists for the development of DM after SWL.
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Association of kidney function and metabolic risk factors with density of glomeruli on renal biopsy samples from living donors.
Mayo Clin. Proc.
PUBLISHED: 04-02-2011
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To test the hypothesis that kidney function and metabolic risk factors are associated with glomerular density on renal biopsy samples from healthy adults.
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Clinical characteristics of potential kidney donors with asymptomatic kidney stones.
Nephrol. Dial. Transplant.
PUBLISHED: 02-01-2011
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Patients with symptomatic kidney stones are characterized by older age, male gender, white race, hypertension, obesity, metabolic syndrome and chronic kidney disease. Whether these characteristics differ in patients with asymptomatic kidney stones is unknown.
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Association between SLC2A9 transporter gene variants and uric acid phenotypes in African American and white families.
Rheumatology (Oxford)
PUBLISHED: 12-24-2010
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SLC2A9 gene variants associate with serum uric acid in white populations, but little is known about African American populations. Since SLC2A9 is a transporter, gene variants may be expected to associate more closely with the fractional excretion of urate, a measure of renal tubular transport, than with serum uric acid, which is influenced by production and extrarenal clearance.
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Kidney function and risk triage in adults: threshold values and hierarchical importance.
Kidney Int.
PUBLISHED: 08-18-2010
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In this study, we attempted to identify threshold values for kidney function measures that maximally discriminate short-term mortality, to identify major population segments in which these thresholds apply, and to classify the hierarchical rank of the thresholds when other classic risk factors are also considered. To do this we retrospectively identified estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (ACR) thresholds to maximize sensitivity and specificity predictions for death in non-institutionalized NHANES III participants, representative of the United States population from 1988 to 1994 and followed through 2000. In a classification tree excluding dichotomizing variables, age 57 years was initially selected; ACR appeared in the second round and eGFR in the third. The prognostic discrimination of optimum eGFR and ACR thresholds exceeded those of commonly advocated public health screening measures, such as LDL cholesterol and fasting blood glucose, with body mass index appearing in the third round, and smoking and LDL cholesterol in the fourth. In a tree permitting dichotomizing variables, the ACR, systolic blood pressure, and glucose first appeared in the third round, with eGFR, smoking, and LDL in the fourth. Thus, the albumin-creatinine ratio and eGFR may be at least as efficient for survival-based clinical triage as most other classic risk factors.
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The association of serum uric acid levels with outcomes following percutaneous coronary intervention.
J Interv Cardiol
PUBLISHED: 07-20-2010
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Serum uric acid may serve as a marker for the activation of oxidative stress and may therefore be a marker for subsequent cardiovascular events. Our goal was to assess the association of serum uric acid levels and the outcomes of patients who have undergone percutaneous coronary intervention (PCI).
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Kidney stones associate with increased risk for myocardial infarction.
J. Am. Soc. Nephrol.
PUBLISHED: 07-08-2010
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Kidney stones are a risk factor for chronic kidney disease (CKD), which, in turn, is a risk factor for myocardial infarction (MI). The objective of this study was to determine whether kidney stones associate with an increased risk for MI. We matched 4564 stone formers (1984 through 2003) on age and gender with 10,860 control subjects among residents in Olmsted County, Minnesota. We identified incident MI by diagnostic codes and validated events by chart review through 2006. We used diagnostic codes to determine incidence of kidney stones and presence of comorbidities (CKD, hypertension, diabetes, obesity, dyslipidemia, gout, alcohol dependence, and tobacco use). During a mean of 9 years of follow-up, stone formers had a 38% (95% confidence interval 7 to 77%) increased risk for MI, which remained at 31% (95% confidence interval 2% to 69%) after adjustment for CKD and other comorbidities. In conclusion, kidney stone formers are at increased risk for MI, and this risk is independent of CKD and other risk factors.
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Shock wave lithotripsy is not predictive of hypertension among community stone formers at long-term followup.
J. Urol.
PUBLISHED: 05-21-2010
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Concern exists over the subsequent development of hypertension after shock wave lithotripsy for the treatment of symptomatic urolithiasis. Referral bias and lack of long-term followup have been limitations of prior studies.
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The association between age and nephrosclerosis on renal biopsy among healthy adults.
Ann. Intern. Med.
PUBLISHED: 05-05-2010
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Chronic kidney disease is common with older age and is characterized on renal biopsy by global glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arteriosclerosis.
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Prevalence of renal artery and kidney abnormalities by computed tomography among healthy adults.
Clin J Am Soc Nephrol
PUBLISHED: 01-14-2010
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Management of incidental renal artery and kidney abnormalities in patients undergoing computed tomography scans is a clinical challenge because their frequency in healthy subjects has not been precisely estimated. Therefore, the prevalence and management of these abnormalities were determined among a large cohort of potential kidney donors undergoing protocol evaluations.
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Development and validation of GFR-estimating equations using diabetes, transplant and weight.
Nephrol. Dial. Transplant.
PUBLISHED: 09-30-2009
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We have reported a new equation (CKD-EPI equation) that reduces bias and improves accuracy for GFR estimation compared to the MDRD study equation while using the same four basic predictor variables: creatinine, age, sex and race. Here, we describe the development and validation of this equation as well as other equations that incorporate diabetes, transplant and weight as additional predictor variables.
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C-reactive Protein among Community-Dwelling Hypertensives on Single-agent Antihypertensive Treatment.
J Am Soc Hypertens
PUBLISHED: 08-14-2009
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C-reactive protein is a predictor of adverse cardiovascular outcomes. The effect of antihypertensive therapy on C-reactive protein levels is largely unknown.
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Risk factors for CKD in persons with kidney stones: a case-control study in Olmsted County, Minnesota.
Am. J. Kidney Dis.
PUBLISHED: 04-06-2009
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Kidney stones are associated with increased risk of chronic kidney disease (CKD); however, risk factors in the general community are poorly defined.
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Kidney stones and the risk for chronic kidney disease.
Clin J Am Soc Nephrol
PUBLISHED: 04-01-2009
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Kidney stones lead to chronic kidney disease (CKD) in people with rare hereditary disorders (e.g., primary hyperoxaluria, cystinuria), but it is unknown whether kidney stones are an important risk factor for CKD in the general population.
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Genome-wide linkage analysis for uric acid in families enriched for hypertension.
Nephrol. Dial. Transplant.
PUBLISHED: 03-03-2009
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Uric acid is heritable and associated with hypertension and insulin resistance. We sought to identify genomic regions influencing serum uric acid in families in which two or more siblings had hypertension.
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Three-dimensional ultrasound bladder characteristics and their association with prostate size and lower urinary tract dysfunction among men in the community.
Urology
PUBLISHED: 02-18-2009
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To characterize ultrasound bladder measures, and to determine whether these measures were associated with measures of lower urinary tract dysfunction.
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Demographic and clinical characteristics associated with glomerular filtration rates in living kidney donors.
Kidney Int.
PUBLISHED: 02-11-2009
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Due to the shortage of organs, living donor acceptance criteria are becoming less stringent. An accurate determination of the glomerular filtration rate (GFR) is critical in the evaluation of living kidney donors and a value exceeding 80 ml/min per 1.73 m(2) is usually considered suitable. To improve strategies for kidney donor screening, an understanding of factors that affect GFR is needed. Here we studied the relationships between donor GFR measured by (125)I-iothalamate clearances (mGFR) and age, gender, race, and decade of care in living kidney donors evaluated at the Cleveland Clinic from 1972 to 2005. We report the normal reference ranges for 1057 prospective donors (56% female, 11% African American). Females had slightly higher mGFR than males after adjustment for body surface area, but there were no differences due to race. The lower limit of normal for donors (5th percentile) was less than 80 ml/min per 1.73 m(2) for females over age 45 and for males over age 40. We found a significant doubling in the rate of GFR decline in donors over age 45 as compared to younger donors. The age of the donors and body mass index increased over time, but their mGFR, adjusted for body surface area, significantly declined by 1.49+/-0.61 ml/min per 1.73 m(2) per decade of testing. Our study shows that age and gender are important factors determining normal GFR in living kidney donors.
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For estimating creatinine clearance measuring muscle mass gives better results than those based on demographics.
Kidney Int.
PUBLISHED: 01-28-2009
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Estimation of creatinine clearance requires knowledge of creatinine generation which can vary in different groups of patients. Since the main source of creatinine is muscle we used dual-energy X-ray absorptiometry to measure the mass of muscle in a cohort of adult men and women in Rochester, Minnesota. Serum and 24 h urinary creatinines were measured directly. The urinary creatinine was estimated using equations based on age and gender and muscle mass in order to calculate creatinine clearance. Among 664 subjects with a mean age of 55+/-20 years, 51% of whom were women, the model fit for urinary creatinine estimated with age and gender (R2=0.359) was similar to that estimated with measured muscle mass (R2=0.359). The likelihood of chronic kidney disease (creatinine clearance of less than 60 ml/min per 1.73 m2) in older subjects was highest with equations that used age, and likelihood of CKD in women was highest with equations that used gender. The outcomes of mortality and cardiovascular disease had stronger associations with decreased creatinine clearance calculated with age and gender than by the clearance calculated with muscle mass. This could be explained by age being a potent predictor of mortality and cardiovascular disease independent of urinary creatinine, muscle mass, and gender. Our study shows that the likelihood of chronic kidney disease in the elderly and in women and the risk of adverse outcomes may be inflated by equations that use patient demographics to estimate creatinine generation.
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Effect of age on the clinical presentation of incident symptomatic urolithiasis in the general population.
J. Urol.
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We characterized variation in the clinical presentation between older and younger first time symptomatic stone formers in the general population.
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Analytic and clinical validation of a standardized cystatin C particle enhanced turbidimetric assay (PETIA) to estimate glomerular filtration rate.
Clin. Chem. Lab. Med.
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Cystatin C is an alternative biomarker for assessing glomerular filtration rate (GFR), yet lack of standardization could hinder its widespread use. In this study we analytically and clinically validated a newer cystatin C particle-enhanced turbidimetric assay (PETIA) traceable to a certified reference material and compared it to the more commonly used particle-enhanced nephelometric assay (PENIA).
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Chronic renovascular hypertension is associated with elevated levels of neutrophil gelatinase-associated lipocalin.
Nephrol. Dial. Transplant.
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Renovascular hypertension (RVH) is characterized by chronic inflammation of the stenotic kidney and progressive renal dysfunction. Neutrophil gelatinase-associated lipocalin (NGAL), an acute phase protein induced in inflammatory conditions and ischemia, is a novel biomarker for acute kidney injury. We hypothesized that chronic RVH would be associated with increased renal and circulating NGAL levels.
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Urolithiasis and the risk of ESRD.
Clin J Am Soc Nephrol
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The contribution of urolithiasis, if any, to the development of ESRD is unclear.
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Association between prior peripherally inserted central catheters and lack of functioning arteriovenous fistulas: a case-control study in hemodialysis patients.
Am. J. Kidney Dis.
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Although an arteriovenous fistula (AVF) is the hemodialysis access of choice, its prevalence continues to be lower than recommended in the United States. We assessed the association between past peripherally inserted central catheters (PICCs) and lack of functioning AVFs.
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Temporal trends in incidence of kidney stones among children: a 25-year population based study.
J. Urol.
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We conducted a population based pediatric study to determine the incidence of symptomatic kidney stones during a 25-year period and to identify factors related to variation in stone incidence during this period.
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The implications of anatomical and functional changes of the aging kidney: with an emphasis on the glomeruli.
Kidney Int.
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Aging is both a natural and inevitable biological process. With advancing age, the kidneys undergo anatomical and physiological changes that are not only the consequences of normal organ senescence but also of specific diseases (such as atherosclerosis or diabetes) that occur with greater frequency in older individuals. Disentangling these two processes, one pathologic and the other physiologic, is difficult. In this review we concentrate on the glomerular structural and functional alterations that accompany natural aging. We also analyze how these changes affect the identification of individuals of advancing age as having chronic kidney disease (CKD) and how these changes can influence prognosis for adverse outcomes, including all-cause mortality, end-stage renal disease, cardiovascular events and mortality, and acute kidney injury. This review describes important shortcomings and deficiencies with our current approach and understanding of CKD in the older and elderly adult.
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Characteristics of renal cystic and solid lesions based on contrast-enhanced computed tomography of potential kidney donors.
Am. J. Kidney Dis.
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The presence of a few renal cysts is considered of little relevance in healthy adults, although acquired renal cystic disease occurs in advanced kidney failure. The objective of this study was to detail renal cystic and solid lesions and identify any association with clinical characteristics.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.