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Find video protocols related to scientific articles indexed in Pubmed.
Cystine nephrolithiasis.
Transl Androl Urol
PUBLISHED: 11-11-2014
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Our understanding of the molecular basis of cystinuria has deepened as the result of the causative genes, SLC3A1 and SLC7A9, being identified. The proteins coded for by these genes form a heterodimer responsible for reabsorption of filtered cystine in the proximal tubule. Failure of this transport system to be targeted to the apical membrane, as in the case of SLC3A1 mutations, or failure of the transport system to function, as in the case of SLC7A9 mutations, leads to abnormal urinary excretion of the relatively insoluble amino acid cystine. Stones and plugs of tubules result, with chronic kidney disease a frequent complication. Here we review the genetics, pathophysiology, pathology, clinical manifestations and clinical management. Increased fluid intake, restriction of sodium and animal protein ingestion, and urinary alkalinization are the standard therapies. Cystine binding thiol drugs tiopronin and D-penicillamine are reserved for patients for whom the conservative therapies are insufficient. New studies of cystine crystal inhibition are highlighted.
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Taxi cab syndrome: a review of the extensive genitourinary pathology experienced by taxi cab drivers and what we can do to help.
Rev Urol
PUBLISHED: 10-23-2014
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This review consolidates knowledge regarding the extensive genitourinary pathology experienced by taxi cab drivers. Taxi cab, livery, truck, and other drivers all objectively and subjectively may have more voiding dysfunction, infertility, urolithiasis, bladder cancer, and urinary infections as compared with nonprofessional drivers; this is called taxi cab syndrome. Together with governmental and medical assistance, simple interventions-such as education, the addition of taxi relief stations, and possibly the use of sanitary urinary collection devices-to curb the progression of genitourinary disease in taxi drivers should be prospectively studied. It is postulated that many of these interventions may also benefit other groups of occupationally related infrequent voiders.
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Association between Kidney Transplant Center Performance and the Survival Benefit of Transplantation Versus Dialysis.
Clin J Am Soc Nephrol
PUBLISHED: 09-18-2014
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Despite the benefits of kidney transplantation, the total number of transplants performed in the United States has stagnated since 2006. Transplant center quality metrics have been associated with a decline in transplant volume among low-performing centers. There are concerns that regulatory oversight may lead to risk aversion and lack of transplantation growth.
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Institutional Characteristics Associated with Receipt of Emergency Care for Obstructive Pyelonephritis at Community Hospitals.
J. Urol.
PUBLISHED: 09-05-2014
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Delivery of recommended care is an important quality measure insufficiently studied within the field of urology. Obstructive pyelonephritis is a suitable case study for this focus because despite guidelines advocating decompression many do not receive such care. We sought to determine the influence of hospital factors, in particular familiarity with urolithiasis, on likelihood of decompression for such patients.
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Evaluation of anatomically designed flocked rectal swabs for molecular detection of enteric pathogens in children admitted to hospital with severe gastroenteritis in botswana.
J. Clin. Microbiol.
PUBLISHED: 08-27-2014
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Two-hundred eighty matched bulk stool and anatomically designed flocked rectal swab samples were collected from children admitted to the hospital with acute diarrhea in Botswana. Their parents were asked about the acceptability of the swab collection method compared with bulk stool sampling. All samples underwent identical testing with a validated 15-target (9 bacterial, 3 viral, and 3 parasite) commercial multiplex PCR assay. The flocked swabs had a 12% higher yield for bacterial pathogen targets (241 versus 212; P = 0.003) compared with that of stool samples, as well as similar yields for viral targets (110 versus 113; P = 0.701) and parasite targets (59 versus 65; P = 0.345). One hundred sixty-four of the flocked swab-stool pairs were also tested with separate laboratory-developed bacterial and viral multiplex assays, and the flocked rectal swabs had a performance that was similar to that seen with commercial assay testing. Almost all parents/guardians found the swabs acceptable. Flocked rectal swabs significantly facilitate the molecular diagnosis of diarrheal disease in children.
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Early childhood diarrhoeal diseases and cognition: are we missing the rest of the iceberg?
Paediatr Int Child Health
PUBLISHED: 08-21-2014
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Risk factors which interfere with cognitive function are especially important during the first 2 years of life - a period referred to as early child development and a time during which rapid growth and essential development occur. Malnutrition, a condition whose effect on cognitive function is well known, has been shown to be part of a vicious cycle with diarrhoeal diseases, and the two pathologies together continue to be the leading cause of illness and death in young children in developing countries. This paper reviews the burden of early childhood diarrhoeal diseases globally and the emerging evidence of their relationship with global disparities in neurocognitive development. The strength of evidence which indicates that the severe childhood diarrhoeal burden may be implicated in cognitive impairment of children from low- and middle-income counties is discussed. Findings suggest that greater investment in multi-site, longitudinal enteric infection studies that assess long-term repercussions are warranted. Furthermore, economic analyses using the concept of human capital should play a key role in advancing our understanding of the breadth and complexities of the health, social and economic ramifications of early childhood diarrhoeal diseases and enteric infections. This broadened awareness can serve to help advocate for more effective interventions, particularly in developing economies.
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Renal transplantations in African Americans: a single-center experience of outcomes and innovations to improve access and results.
Urology
PUBLISHED: 07-01-2014
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To report a single-center 10-year experience of outcomes of kidney transplantation in African Americans (AAs) vs Caucasian Americans (CA) and to propose ways in which to improve kidney transplant outcomes in AAs, increased access to kidney transplantation, prevention of kidney disease, and acceptance of organ donor registration rates in AAs.
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Risk of chronic and end stage kidney disease in patients with nephrolithiasis.
J. Urol.
PUBLISHED: 06-04-2014
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We examine kidney stone disease as a potential risk factor for chronic kidney disease, end stage kidney disease and treatment with dialysis.
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Guidelines for reporting case studies on extracorporeal treatments in poisonings: methodology.
Semin Dial
PUBLISHED: 05-29-2014
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A literature review performed by the EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup highlighted deficiencies in the existing literature, especially the reporting of case studies. Although general reporting guidelines exist for case studies, there are none in the specific field of extracorporeal treatments in toxicology. Our goal was to construct and propose a checklist that systematically outlines the minimum essential items to be reported in a case study of poisoned patients undergoing extracorporeal treatments. Through a modified two-round Delphi technique, panelists (mostly chosen from the EXTRIP workgroup) were asked to vote on the pertinence of a set of items to identify those considered minimally essential for reporting complete and accurate case reports. Furthermore, independent raters validated the clarity of each selected items between each round of voting. All case reports containing data on extracorporeal treatments in poisoning published in Medline in 2011 were reviewed during the external validation rounds. Twenty-one panelists (20 from the EXTRIP workgroup and an invited expert on pharmacology reporting guidelines) participated in the modified Delphi technique. This group included journal editors and experts in nephrology, clinical toxicology, critical care medicine, emergency medicine, and clinical pharmacology. Three independent raters participated in the validation rounds. Panelists voted on a total of 144 items in the first round and 137 items in the second round, with response rates of 96.3% and 98.3%, respectively. Twenty case reports were evaluated at each validation round and the independent raters' response rate was 99.6% and 98.8% per validation round. The final checklist consists of 114 items considered essential for case study reporting. This methodology of alternate voting and external validation rounds was useful in developing the first reporting guideline for case studies in the field of extracorporeal treatments in poisoning. We believe that this guideline will improve the completeness and transparency of published case reports and that the systematic aggregation of information from case reports may provide early signals of effectiveness and/or harm, thereby improving healthcare decision-making.
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Chylous ascites after laparoscopic donor nephrectomy.
Asian J Endosc Surg
PUBLISHED: 05-15-2014
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The aim of this study was to determine the incidence, presentation, management, and outcomes of chylous ascites following laparoscopic donor nephrectomy.
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Continuous transversus abdominis plane block catheter analgesia for postoperative pain control in renal transplant.
J Anesth
PUBLISHED: 05-11-2014
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Continuous transversus abdominis plane (TAP) block using a catheter has proven its usefulness in reducing opioid requirements and pain scores after lower abdominal surgery. However, there are no reports of its successful use after renal transplant. We tested the hypothesis that continuous TAP block would retrospectively reduce opioid requirement, nausea score and hospital stay after renal transplant surgery.
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Medical management of kidney stones: AUA guideline.
J. Urol.
PUBLISHED: 05-05-2014
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The purpose of this guideline is to provide a clinical framework for the diagnosis, prevention and follow-up of adult patients with kidney stones based on the best available published literature.
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Twice-weekly and incremental hemodialysis treatment for initiation of kidney replacement therapy.
Am. J. Kidney Dis.
PUBLISHED: 04-03-2014
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Mortality is highest in the first months of maintenance hemodialysis (HD) therapy. In many Western countries, patients who transition to kidney replacement therapy usually begin thrice-weekly HD regardless of their level of residual kidney function (RKF). RKF is a major predictor of survival. RKF may decline more rapidly with thrice-weekly HD treatments, is associated with a reduced need for dialytic solute clearance, and is an important factor in the prescription of peritoneal dialysis. In this article, we review the concept of incremental HD, in which weekly dialysis dose, in particular HD treatment frequency, is based on a variety of clinical factors, such as RKF (including urine output > 0.5 L/d), volume status, cardiovascular symptoms, body size, potassium and phosphorus levels, nutritional status, hemoglobin level, comorbid conditions, hospitalizations, and health-related quality of life. These 10 clinical criteria may identify which patients might benefit from beginning maintenance HD therapy twice weekly. Periodic monitoring of these criteria will determine the timing for increasing dialysis dose and frequency. We recognize that twice-weekly HD represents a major paradigm shift for many clinicians and jurisdictions. Therefore, we propose conducting randomized controlled trials of twice-weekly versus thrice-weekly HD to assess the potential of twice-weekly HD to improve survival and health-related quality of life while simultaneously reducing costs, protecting fragile vascular accesses, and optimizing resource use during the first year of hemodialysis therapy. Such incremental and individualized HD therapy may prove to be the most appropriate approach for transitioning to dialytic therapy.
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Facilitating the transition from physiology to hospital wards through an interdisciplinary case study of septic shock.
BMC Med Educ
PUBLISHED: 03-26-2014
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In order to develop clinical reasoning, medical students must be able to integrate knowledge across traditional subject boundaries and multiple disciplines. At least two dimensions of integration have been identified: horizontal integration, bringing together different disciplines in considering a topic; and vertical integration, bridging basic science and clinical practice. Much attention has been focused on curriculum overhauls, but our approach is to facilitate horizontal and vertical integration on a smaller scale through an interdisciplinary case study discussion and then to assess its utility.
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Utilization of vascular conduits to facilitate renal transplantation in patients with significant aortoiliac calcification.
Urology
PUBLISHED: 03-21-2014
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To describe the use of vascular conduits (donor iliac artery or saphenous vein) in renal transplantation recipients with extensive aortoiliac calcification.
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Low Testosterone at Time of Transplantation is Independently Associated with Poor Patient and Graft Survival in Male Renal Transplant Recipients.
J. Urol.
PUBLISHED: 03-21-2014
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Low testosterone is common in men with renal disease and it increases the risk of death in those on dialysis. We studied serum testosterone at transplantation and correlated it with patient and graft outcomes.
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Treatment of calcium nephrolithiasis in the patient with hyperuricosuria.
J. Nephrol.
PUBLISHED: 03-18-2014
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Nearly one-third of patients with calcium stones have hyperuricosuria. In vitro studies and clinical trials have investigated the relationship between uric acid and calcium stones, but the association between hyperuricosuria and calcium stone formation in patients is still being debated. Uric acid appears to cause salting out of calcium oxalate in human urine. However, the importance of this in vitro phenomenon to the proposed association is not supported in cross-sectional observational studies. A small placebo-controlled randomized clinical trial showed that allopurinol decreased the rate of recurrent calcium oxalate calculi in patients with hyperuricosuria and normocalciuria. An assessment of the effect of combination therapy of allopurinol with indapamide showed no additive effect. Allopurinol may have antioxidant effects that are responsible for its reducing calcium stone formation, which are independent of xanthine oxidase inhibition. In addition, a newer xanthine oxidoreductase inhibitor, febuxostat, may also be effective in the prevention of calcium stones, as it reduces urinary uric acid excretion.
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Urinary lithogenic risk profile in recurrent stone formers with hyperoxaluria: a randomized controlled trial comparing DASH (Dietary Approaches to Stop Hypertension)-style and low-oxalate diets.
Am. J. Kidney Dis.
PUBLISHED: 02-25-2014
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Patients with nephrolithiasis and hyperoxaluria generally are advised to follow a low-oxalate diet. However, most people do not eat isolated nutrients, but meals consisting of a variety of foods with complex combinations of nutrients. A more rational approach to nephrolithiasis prevention would be to base dietary advice on the cumulative effects of foods and different dietary patterns rather than single nutrients.
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Hospitalizations following living donor nephrectomy in the United States.
Clin J Am Soc Nephrol
PUBLISHED: 01-23-2014
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Living donors represented 43% of United States kidney donors in 2012. Although research suggests minimal long-term consequences of donation, few comprehensive longitudinal studies for this population have been performed. The primary aims of this study were to examine the incidence, risk factors, and causes of rehospitalization following donation.
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Symptomatic central venous stenosis in a hemodialysis patient leading to loss of arteriovenous access: a case report and literature review.
Nephron Extra
PUBLISHED: 01-01-2014
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Central venous stenosis is a well-described sequel to the placement of hemodialysis catheters in the central venous system. The presence of an ipsilateral arteriovenous fistula or graft often leads to severe venous dilatation, arm edema and recurrent infections. Vascular access thrombosis, compromised blood flow and inadequate dialysis delivery are dreaded complications that eventually render the access unusable. We report the case of a 58-year-old male hemodialysis patient who developed symptomatic central venous stenosis to illustrate the problem and review the pertinent literature. This patient developed severe enlargement of upper extremity veins due to central venous stenosis. The symptoms were refractory to multiple endovascular interventions and eventually necessitated ligation of his arteriovenous fistula. Central venous stenosis remains a pervasive problem despite advances in our understanding of its etiology and recognition of the enormity of its consequences. Due to the lack of effective therapeutic options, prevention is better than cure.
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Impact of mild chronic hyponatremia on falls, fractures, osteoporosis, and death.
Am J. Orthop.
PUBLISHED: 12-17-2013
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There is emerging evidence that mild chronic hyponatremia (MCH), highly prevalent in the elderly and once considered asymptomatic, is a major independent risk factor for falls, fall-related fractures (independent of osteoporosis, age, and sex), impaired attention and gait, reductions in bone mineral density (BMD), and even death. Although research on MCH and bone health is emerging and ongoing, it has not been recognized in orthopedics. Orthopedic surgeons must be educated regarding the impact of hyponatremia on bone, as osteoporotic fractures have enormous socioeconomic consequences, and the problem will worsen. Orthopedic surgeons should also be included in research, in education, and in the establishment of diagnostic and treatment protocols. In this article, we review the current concepts of MCH and its impacts on the skeletal system.
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Radioisotope blood volume measurement in hemodialysis patients.
Hemodial Int
PUBLISHED: 11-22-2013
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Accurate assessment of blood volume (BV) may be helpful for prescribing hemodialysis (HD) and for reducing complications related to hypovolemia and volume overload. Monitoring changes in relative BV (RBV) using hematocrit, e.g., Crit-Line Monitor (CLM-III), an indirect method, cannot be used to determine absolute BV. We report the first study of BV measurement for assessing volume status in HD patients using the indicator dilutional method. Ten adult HD patients were enrolled in this prospective observational study. BV measurement was performed before and after HD using BV analysis (BVA)-100 (Daxor Corporation, New York, NY, USA). BVA-100 calculates BV using radiolabeled albumin (Iodine-131) followed by serial measures of the radioisotope. Fluid loss from the extravascular space was calculated by subtracting the change in BV from total weight loss. Intradialytic changes in RBV were measured by CLM-III. Eight out of 10 cases had significant hypervolemia, two cases were normovolemic. The range of BV variation from predicted normal was 156 to 1990?mL. Significant inter-individual differences in extravascular space fluid loss ranged from 54% to 99% of total weight loss. Spearman correlation showed a good correlation in the measurement of RBV by BVA-100 and CLM-III in 8 out of 10 patients (r(2) ?=?0.64). BV measurement using BVA-100 is useful to determine absolute BV as well as changes in BV and correlates reasonably well with CLM-III measurements. Individual refilling ability can be determined as well. This may prove useful in prescribing and monitoring ultrafiltration rates, establishment of optimal BV in HD patients and reducing morbidity and mortality associated with chronic HD.
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Stone disease in living-related renal donors: long-term outcomes for transplant donors and recipients.
J. Endourol.
PUBLISHED: 11-21-2013
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Abstract Background and Purpose: Historically, patients wishing to donate their kidney to living related recipients were deemed ineligible if preoperative imaging demonstrated nephrolithiasis. We assess the outcomes of donors with nephrolithiasis and the outcomes of their recipients. Methods: Donors undergoing nephrectomy between 2001 and 2011 who had nephrolithiasis on preoperative computed tomography (CT) imaging or a history of stone passage were identified. A retrospective chart review documented donor and recipient demographics, donor 24-hour urine collections, stone size and location, stone events after transplant, and graft function. A seven-question telephone survey regarding development and/or presence of symptomatic nephrolithiasis was conducted. Results: Fifty-four donor-recipient pairs met the inclusion criteria. Twenty-eight (51.9%) patients had valid preoperative 24-hour urine collection, seven (25%) of whom had hypercalciuria. Seven (13%) patients had previous symptomatic nephrolithiasis, but no stones on imaging. Forty-one patients donated a kidney with at least one stone, with a mean stone size of 2.4?mm (range 1-6?mm). Median follow-up for donors and recipients was 22.5 months (interquartile range [IQR] 1-79.3) and 47.4 months (IQR 25.1-76.1), with 50% and 77.7% having a follow-up of more than 2 years, respectively. One donor with nephrolithiasis on preoperative imaging who donated the contralateral kidney passed a stone spontaneously after visiting the emergency department. Otherwise, no other donors or recipients experienced any stone episodes during the follow-up period. Conclusion: The risk of clinical stone recurrence in donors and recipients is low: As such, presence of small caliceal stones should not constitute an exclusion for living-related kidney donation.
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Development and evaluation of global child health educational modules.
Pediatrics
PUBLISHED: 11-11-2013
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To determine if a standardized global child health (GCH) modular course for pediatric residents leads to satisfaction, learning, and behavior change.
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Comorbidity burden and perioperative complications for living kidney donors in the United States.
Clin J Am Soc Nephrol
PUBLISHED: 09-26-2013
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Since 1998, 35% of kidney transplants in the United States have been derived from living donors. Research suggests minimal long-term health consequences after donation, but comprehensive studies are limited. The primary objective was to evaluate trends in comorbidity burden and complications among living donors.
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Dialysis initiation: whats the rush?
Semin Dial
PUBLISHED: 09-19-2013
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The recent trend to early initiation of dialysis (at eGFR >10 ml/min/1.73 m(2) ) appears to have been based on conventional wisdoms that are not supported by evidence. Observational studies using administrative databases report worse comorbidity-adjusted dialysis survival with early dialysis initiation. Although some have concluded that the IDEAL randomized controlled trial of dialysis start provided evidence that patients become symptomatic with late dialysis start, there is no definitive support for this view. The potential harms of early start of dialysis, including the loss of residual renal function (RRF), have been well documented. The rate of RRF loss (renal function trajectory) is an important consideration for the timing of the dialysis initiation decision. Patients with low glomerular filtration rate (GFR) may have sufficient RRF to be maintained off dialysis for years. Delay of dialysis start until a working arterio-venous access is in place seems prudent in light of the lack of harm and possible benefit of late dialysis initiation. Prescribing frequent hemodialysis is not recommended when dialysis is initiated early. The benefits of early initiation of chronic dialysis after episodes of congestive heart failure or acute kidney injury require further study. There are no data to show that early start benefits diabetics or other patient groups. Preemptive start of dialysis in noncompliant patients may be necessary to avoid complications. The decision to initiate dialysis requires informed patient consent and a joint decision by the patient and dialysis provider. Possible talking points for obtaining informed consent are provided.
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Health-related quality of life (HRQoL) in cystine compared with non-cystine stone formers.
Urolithiasis
PUBLISHED: 09-18-2013
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Cystinuria is a genetic cause of recurrent kidney stones which may be more recurrent and larger than more common non-cystine stones. They may have a greater impact on health-related quality of life (HRQoL). We measured this impact by surveying HRQoL in patients with stones, comparing non-cystine stone formers (NCSF) to cystine stone formers (CYSF) and both groups to normative values of the US population. We used SF-36v2 via an internet instrument. CYSF patients were recruited via cystinuria-related websites, two patient advocacy groups, and an active endourology practice. NCSF patients were recruited from the same practice and by email. Total n surveyed with scorable data: 214 CYSF and 81 NCSF. The participants included 128 men and 161 women. The group of CYSF were significantly younger (39 vs. 54 years) and suffered longer from kidney stones (255 vs. 136 months). CYSF patients had significantly more episodes of stones than NCSF patients in the last year (N = 108 CYSF, N = 20 NCSF). More frequent stones in the last year and mental comorbidities most often predicted worse scores in the individual HRQoL domains. However, cystine stone composition was a significant predictor of worse scores only for role emotional. Better scores in all SF-36 domains were associated with greater time since the last kidney stone event. Although kidney stones are often transient, kidney stone formers, regardless of stone composition, have a worse HRQoL than the standard US population, which has a normative score of 50, such as general health (41.2 ± 12.8), bodily pain (46.5 ± 11.8) and mental health (45.1 ± 12.6). CYSF are more frequent and severe stone formers compared with NCSF with a resulting greater, direct impact on the HRQoL of CYSF patients. Whether preventive strategies for cystinuria are being properly utilized by practitioners, and which strategies are most effective, should be established.
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STONE DISEASE IN LIVING-RELATED RENAL DONORS: LONG-TERM OUTCOMES FOR TRANSPLANT DONORS AND RECIPIENTS.
J. Endourol.
PUBLISHED: 09-04-2013
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Introduction: Historically patients wishing to donate their kidney to living related recipients were deemed ineligible if pre-operative imaging demonstrated nephrolithiasis. We assess the outcomes of donors with nephrolithiasis and the outcomes of their recipients. Methods: Donors undergoing nephrectomy between 2001-2011 who had nephrolithiasis on preoperative CT imaging or a history of stone passage were identified. A retrospective chart review documented donor and recipient demographics, donor 24-hour urine collections, stone size and location, stone events following transplant and graft function. A 7-question telephone survey regarding development and/or presence of symptomatic nephrolithiasis was conducted. Results: 54 donor-recipient pairs met the inclusion criteria. Twenty-eight (51.9%) patients had valid pre-operative 24-hour urine collection, seven (25%) of which had hypercalciuria. Seven (13%) patients had previous symptomatic nephrolithiasis, but no stones on imaging. 41 patients donated a kidney with at least one stone, with a mean stone size of 2.4 mm (range 1-6 mm). Median follow-up for donors and recipients was 22.5 months [IQR 1 - 79.3] and 47.4 months [IQR 25.1 - 76.1], with 50% and 77.7% having a follow-up of more than two years, respectively. One donor with nephrolithiasis on pre-operative imaging who donated the contralateral kidney passed a stone spontaneously after visiting the emergency room. Otherwise, no other donors or recipients experienced any stone episodes during the follow-up period. Conclusion: The risk of clinical stone recurrence in donors and recipients is low: as such, presence of small caliceal stones should not constitute an exclusion for living-related kidney donation.
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Randomized controlled trial of febuxostat versus allopurinol or placebo in individuals with higher urinary uric acid excretion and calcium stones.
Clin J Am Soc Nephrol
PUBLISHED: 08-08-2013
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Higher urinary uric acid excretion is a suspected risk factor for calcium oxalate stone formation. Febuxostat, a xanthine oxidoreductase inhibitor, is effective in lowering serum urate concentration and urinary uric acid excretion in healthy volunteers and people with gout. This work studied whether febuxostat, compared with allopurinol and placebo, would reduce 24-hour urinary uric acid excretion and prevent stone growth or new stone formation.
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Evaluation of a Case-based Urology Learning Program.
Urology
PUBLISHED: 06-26-2013
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To address the challenges that todays trainees encounter, such as information overload and reduced immersion in the field, and recognizing their preference for novel educational resources, an electronic case-based urology learning program was developed. Each case was designed to illustrate the basic principles of the disease process and the fundamentals of evaluation and management using the Socratic method, recapitulating a prototypical patient encounter.
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KDOQI US commentary on the 2012 KDIGO Clinical Practice Guideline for Anemia in CKD.
Am. J. Kidney Dis.
PUBLISHED: 06-24-2013
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The 2012 KDIGO (Kidney Disease: Improving Global Outcomes) Clinical Practice Guideline for Anemia in Chronic Kidney Disease provides clinicians with comprehensive evidence-based recommendations to improve patient care. In this commentary, we review these recommendations and the underlying evidence. Most recommendations are well reasoned. For some, the evidence is unclear and recommendations require some qualification. While the KDIGO guideline stresses the potential risks of intravenous iron therapy, withholding iron might have its own risks. The recommendation to avoid hemoglobin levels falling below 9 g/dL sets a lower bound of "acceptability" that may increase blood transfusion. Given the lack of research supporting the optimal transfusion strategy for end-stage renal disease patients, it is difficult to weigh the risks and benefits of red blood cell transfusion. We find a paucity of evidence that hemoglobin concentration targeted between 11 and 11.5 g/dL is associated with a safety risk. Although the evidence that erythropoiesis-stimulating agent use improves patient quality of life is poor, it is possible that the instruments used to measure quality of life may not be well attuned to the needs of chronic kidney disease or dialysis patients. Our last section focuses specifically on the recommendations to treat anemia in children.
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Update on cystinuria.
Curr. Opin. Nephrol. Hypertens.
PUBLISHED: 05-14-2013
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Cystinuria is a rare genetic disease with increased urinary excretion of the poorly soluble amino acid cystine. It can lead to significant morbidity in affected patients due to the often large and recurrent resulting kidney stones. Treatment is focused on the prevention of stone formation. There have been few advances in the available therapeutic options for the disorder in the last 15-20 years.
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Severe late-onset multisystem cytomegalovirus infection in a premature neonate previously treated for congenital infection.
BMC Pediatr
PUBLISHED: 04-19-2013
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Cytomegalovirus is the most common pathogen causing congenital infection and can result in significant neurodevelopmental adverse outcomes. For this reason, it is the standard of care in many regions to treat congenital cytomegalovirus infection involving the brain with six weeks of ganciclovir. There have been no reports in the published literature of significant cytomegalovirus neonatal infection in infants previously treated for congenital infection.
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Health status and quality of life in patients with stable coronary artery disease and chronic kidney disease treated with optimal medical therapy or percutaneous coronary intervention (post hoc findings from the COURAGE trial).
Am. J. Cardiol.
PUBLISHED: 04-15-2013
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Chronic kidney disease (CKD) is an important clinical co-morbidity that increases the risk of death and myocardial infarction in patients with coronary artery disease (CAD) even when treated with guideline-directed therapies. It is unknown, however, whether CKD influences the effects of CAD treatments on patients health status, their symptoms, function, and quality of life. We performed a post hoc analysis of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) study to compare health status in patients with stable CAD with and without CKD defined as a glomerular filtration rate of <60 ml/min/1.73 m(2) randomized to either percutaneous coronary intervention (PCI) and optimal medical therapy (OMT) or OMT alone. Health status was measured at baseline, 1, 3, 6, 12, 24, and 36 months of follow-up with the Seattle Angina Questionnaire in 310 patients with CKD and 1,719 patients without CKD. Linear mixed-effects models were used to analyze Seattle Angina Questionnaire scores longitudinally. Mean scores for angina-related quality of life, angina frequency, and physical limitation domains improved from baseline values in both patients with and without CKD and plateaued. Early improvement (1 to 6 months) was more common in patients treated with PCI plus OMT than with OMT alone in both patients with and without CKD. Treatment satisfaction scores were high at baseline in all groups and did not change significantly over time. In conclusion, although CKD is an important determinant of event-free survival in patients with stable CAD, it neither precludes satisfactory treatment of angina with PCI plus OMT or OMT alone nor is it associated with an unsatisfactory quality of life.
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Contrasting patterns of viral load response in transplant recipients with BK polyomavirus DNAemia on leflunomide therapy.
Clin Transplant
PUBLISHED: 04-03-2013
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Reduction in immunosuppression is considered the therapy of proven benefit for BKV infection in renal transplantation, but the use of leflunomide has also been reported. It was observed at this center that the patterns of viral load response while on leflunomide appear to fall into two distinct types.
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Optimum nutrition for kidney stone disease.
Adv Chronic Kidney Dis
PUBLISHED: 02-27-2013
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We summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. The therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. The mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. For cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development.
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Which skills really matter? proving face, content, and construct validity for a commercial robotic simulator.
Surg Endosc
PUBLISHED: 02-07-2013
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A novel computer simulator is now commercially available for robotic surgery using the da Vinci(®) System (Intuitive Surgical, Sunnyvale, CA). Initial investigations into its utility have been limited due to a lack of understanding of which of the many provided skills modules and metrics are useful for evaluation. In addition, construct validity testing has been done using medical students as a "novice" group-a clinically irrelevant cohort given the complexity of robotic surgery. This study systematically evaluated the simulators skills tasks and metrics and established face, content, and construct validity using a relevant novice group.
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Nanolitre real-time PCR detection of bacterial, parasitic, and viral agents from patients with diarrhoea in Nunavut, Canada.
Int J Circumpolar Health
PUBLISHED: 02-05-2013
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Little is known about the microbiology of diarrhoeal disease in Canadas Arctic regions. There are a number of limitations of conventional microbiology testing techniques for diarrhoeal pathogens, and these may be further compromised in the Arctic, given the often long distances for specimen transport.
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Evidence for inheritance of medullary sponge kidney.
Kidney Int.
PUBLISHED: 02-01-2013
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Medullary sponge kidney (MSK) is associated with recurrent calcium stones. Gambaros group evaluated the relatives of probands with MSK. When prior imaging was not available, they performed renal ultrasounds. They demonstrated familial clustering, providing the best evidence yet that MSK is a heritable disorder. Although a small proportion of MSK cases are associated with variants of glial cell-derived neurotrophic factor (GDNF), the genetic basis for most instances of MSK is not known.
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Microbiology of urinary tract infections in Gaborone, Botswana.
PLoS ONE
PUBLISHED: 01-25-2013
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The microbiology and epidemiology of UTI pathogens are largely unknown in Botswana, a high prevalence HIV setting. Using laboratory data from the largest referral hospital and a private hospital, we describe the major pathogens causing UTI and their antimicrobial resistance patterns.
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Hospital-based surveillance for rotavirus gastroenteritis using molecular testing and immunoassay during the 2011 season in Botswana.
Pediatr. Infect. Dis. J.
PUBLISHED: 01-24-2013
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We describe rotavirus testing and clinical characteristics for children admitted with acute gastroenteritis during Botswanas 2011 rotavirus season. The rotavirus season extended from June to October with rotavirus-specific case fatality being 2.8%. Using molecular testing as reference, the immunochromatographic test had a sensitivity of 76.5% and specificity of 68.0%. Rotavirus vaccine may significantly reduce childhood morbidity and mortality in Botswana.
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Pharmacologic treatment of kidney stone disease.
Urol. Clin. North Am.
PUBLISHED: 01-23-2013
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This article reviews the data on pharmacologic treatment of kidney stone disease, with a focus on prophylaxis against stone recurrence. One of the most effective and important therapies for stone prevention, an increase in urine volume, is not discussed because this is a dietary and not a pharmacologic intervention. Also reviewed are medical expulsive therapy used to improve the spontaneous passage of ureteral stones and pharmacologic treatment of symptoms associated with ureteral stents. The goal is to review the literature with a focus on the highest level of evidence (ie, randomized controlled trials).
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Hereditary causes of kidney stones and chronic kidney disease.
Pediatr. Nephrol.
PUBLISHED: 01-20-2013
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Adenine phosphoribosyltransferase (APRT) deficiency, cystinuria, Dent disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC), and primary hyperoxaluria (PH) are rare but important causes of severe kidney stone disease and/or chronic kidney disease in children. Recurrent kidney stone disease and nephrocalcinosis, particularly in pre-pubertal children, should alert the physician to the possibility of an inborn error of metabolism as the underlying cause. Unfortunately, the lack of recognition and knowledge of the five disorders has frequently resulted in an unacceptable delay in diagnosis and treatment, sometimes with grave consequences. A high index of suspicion coupled with early diagnosis may reduce or even prevent the serious long-term complications of these diseases. In this paper, we review the epidemiology, clinical features, diagnosis, treatment, and outcome of patients with APRT deficiency, cystinuria, Dent disease, FHHNC, and PH, with an emphasis on childhood manifestations.
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A pilot study of the effect of sodium thiosulfate on urinary lithogenicity and associated metabolic acid load in non-stone formers and stone formers with hypercalciuria.
PLoS ONE
PUBLISHED: 01-01-2013
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Sodium thiosulfate (STS) reduced calcium stone formation in both humans and genetic hypercalciuric stone forming (GHS) rats. We sought to measure urine chemistry changes resulting from STS administration in people. DESIGN SETTING PARTICIPANTS MEASUREMENTS: STS was given to healthy and hypercalciuric stone forming adults. Five normal non-stone forming adults (mean age 33 years), and 5 people with idiopathic hypercalciuria and calcium kidney stones (mean age 66 years) participated. Two baseline 24-hour urine collections were performed on days 2 and 3 of 3 days of self-selected diets. Subjects then drank STS 10 mmol twice a day for 7 days and did urine collections while repeating the self-selected diet. Results were compared by non-parametric Wilcoxon signed rank test. The primary outcome was the resulting change in urine chemistry.
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Implications of a reduction in the hemoglobin target in erythropoiesis-stimulating agent-treated hemodialysis patients.
Nephron Extra
PUBLISHED: 11-11-2011
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Patients treated with erythropoiesis-stimulating agents (ESAs) to a hemoglobin (Hb) level >12.0 g/dl have increased risk of multiple complications, including death. The optimal Hb target for ESA use has not been established. We hypothesized that reducing the target Hb would prevent levels >12 g/dl and lead to significant cost savings.
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Oral antibiotic treatment of Helicobacter pylori leads to persistently reduced intestinal colonization rates with Oxalobacter formigenes.
J. Endourol.
PUBLISHED: 10-21-2011
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Oxalobacter formigenes (OF) may play a protective role in preventing calcium oxalate stones. This is the first prospective study to evaluate the effect of antibiotics on OF colonization. Intestinal colonization by OF is associated with reduced urinary oxalate excretion. Exposure to antibiotics may be an important factor determining rates of colonization.
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Coherent NMR Stark spectroscopy.
J. Magn. Reson.
PUBLISHED: 09-23-2011
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We demonstrate phase-coherent Stark effects from a radiofrequency E field at twice the NMR frequency (2?(0)) of (69)Ga in GaAs. The 2?(0) phase (?(E)) selects component responses from the nuclear quadrupole Hamiltonian (H(Q)). This is possible by synchronizing few-?s 2?(0) pulses with an NMR line-narrowing sequence, which averages the Stark interaction to dominate spectra on a background with 10(3)× enhanced resolution. Spectra vs ?(E) reveal relative sizes of tensorial factors in H(Q). Comparative modeling and numerical simulations evaluate spectral features unexplained by average Hamiltonian theory, and suggest improvements for quantitative calibration of individual response components. Application of this approach to bulk samples is of value to define Stark responses that may later be used to interrogate the internal electrostatics of structured samples.
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Medication adherence assessment in a clinical trial with centralized follow-up and direct-to-patient drug shipments.
Clin Trials
PUBLISHED: 08-03-2011
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Assessment of adherence to study medications is a common challenge in clinical research. Counting unused study medication is the predominant method by which adherence is assessed in outpatient clinical trials but it has limitations that include questionable validity and burdens on research personnel.
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Potential pharmacologic treatments for cystinuria and for calcium stones associated with hyperuricosuria.
Clin J Am Soc Nephrol
PUBLISHED: 07-14-2011
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Two new potential pharmacologic therapies for recurrent stone disease are described. The role of hyperuricosuria in promoting calcium stones is controversial with only some but not all epidemiologic studies demonstrating associations between increasing urinary uric acid excretion and calcium stone disease. The relationship is supported by the ability of uric acid to "salt out" (or reduce the solubility of) calcium oxalate in vitro. A randomized, controlled trial of allopurinol in patients with hyperuricosuria and normocalciuria was also effective in preventing recurrent stones. Febuxostat, a nonpurine inhibitor of xanthine oxidase (also known as xanthine dehydrogenase or xanthine oxidoreductase) may have advantages over allopurinol and is being tested in a similar protocol, with the eventual goal of determining whether urate-lowering therapy prevents recurrent calcium stones. Treatments for cystinuria have advanced little in the past 30 years. Atomic force microscopy has been used recently to demonstrate that effective inhibition of cystine crystal growth is accomplished at low concentrations of l-cystine methyl ester and l-cystine dimethyl ester, structural analogs of cystine that provide steric inhibition of crystal growth. In vitro, l-cystine dimethyl ester had a significant inhibitory effect on crystal growth. The drugs safety and effectiveness will be tested in an Slc3a1 knockout mouse that serves as an animal model of cystinuria.
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Rapid PCR detection of group A Streptococcus from flocked throat swabs: a retrospective clinical study.
Ann. Clin. Microbiol. Antimicrob.
PUBLISHED: 05-16-2011
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Rapid diagnosis of GAS pharyngitis may improve patient care by ensuring that patients with GAS pharyngitis are treated quickly and also avoiding unnecessary use of antibiotics in those without GAS infection. Very few molecular methods for detection of GAS in clinical throat swab specimens have been described.
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Febuxostat in gout: serum urate response in uric acid overproducers and underexcretors.
J. Rheumatol.
PUBLISHED: 05-15-2011
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Hyperuricemia of gout can arise due to either overproduction or underexcretion of uric acid. Not all available urate-lowering therapies are equally effective and safe for use in patients with renal disease. The objective of this post-hoc analysis was to determine the effectiveness of the xanthine oxidase inhibitor febuxostat in reducing serum urate (sUA) levels in gouty patients who were either overproducers or underexcretors.
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Global evaluative assessment of robotic skills: validation of a clinical assessment tool to measure robotic surgical skills.
J. Urol.
PUBLISHED: 05-10-2011
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We developed and validated a standardized assessment tool for robotic surgical skills, and report its usefulness, reliability and construct validity in a clinical setting.
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Effect of diet orange soda on urinary lithogenicity.
Urol. Res.
PUBLISHED: 04-28-2011
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Studies have shown that certain beverages decrease urinary lithogenicity by increasing urine citrate excretion. Diet Sunkist Orange soda had the highest concentration of citrate and total alkali content among 12 diet sodas previously assayed. We studied the effect of Diet Sunkist Orange soda consumption on urinary chemistry. Nine healthy men and women ages 26-54 years completed the study. During the control period, subjects drank 36 oz of water for 3 days in addition to their own, self-selected diet and recorded a food diary. During the study period, the subjects drank three 12-oz cans of Diet Sunkist Orange soda a day instead of water, and replicated their diets from the control period. In each period, the subjects performed 24-h urine collections on days 2 and 3. Urine chemical analysis was performed, including urinary citrate levels and pH. Diet Sunkist Orange soda increased urinary citrate excretion by 60 mg/day, which was not statistically significant (95% CI -75 to 195, P value 0.34). There was no significant change in pH from the control period to the study period (pH: 6.29-6.21; 95% CI: -0.09 to 0.25, P = 0.30). Urine volumes and creatinine excretions were not significantly different between the control and study periods. Despite the relatively high citrate and total alkali content of Diet Sunkist Orange soda, the volume consumed in this study (36 oz per day) did not provide sufficient potential base to significantly alter urine composition in healthy subjects with normocitraturia. The effect of Diet Sunkist Orange soda on urinary chemistry in patients with hypocitraturia and nephrolithiasis is not likely to have a clinically significant effect to prevent calcium or uric acid stones.
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Patient participation in research among solid organ transplant recipients in the United States.
Transplantation
PUBLISHED: 04-26-2011
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In many healthcare contexts, evidence exists that patients who participate in research protocols (PRP) significantly differ from nonparticipants. These differences may affect the external validity of study findings, reflect access to care, and potentially explain sources of difference in patient outcomes. There is no comprehensive study evaluating PRP among transplant recipients.
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Ambient temperature as a contributor to kidney stone formation: implications of global warming.
Kidney Int.
PUBLISHED: 03-30-2011
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Nephrolithiasis is a common disease across the world that is becoming more prevalent. Although the underlying cause for most stones is not known, a body of literature suggests a role of heat and climate as significant risk factors for lithogenesis. Recently, estimates from computer models predicted up to a 10% increase in the prevalence rate in the next half century secondary to the effects of global warming, with a coinciding 25% increase in health-care expenditures. Our aim here is to critically review the medical literature relating stones to ambient temperature. We have categorized the body of evidence by methodology, consisting of comparisons between geographic regions, comparisons over time, and comparisons between people in specialized environments. Although most studies are confounded by other factors like sunlight exposure and regional variation in diet that share some contribution, it appears that heat does play a role in pathogenesis in certain populations. Notably, the role of heat is much greater in men than in women. We also hypothesize that the role of a significant human migration (from rural areas to warmer, urban locales beginning in the last century and projected to continue) may have a greater impact than global warming on the observed worldwide increasing prevalence rate of nephrolithiasis. At this time the limited data available cannot substantiate this proposed mechanism but further studies to investigate this effect are warranted.
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Melamine-related kidney stones and renal toxicity.
Nat Rev Nephrol
PUBLISHED: 03-22-2011
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Several well-documented outbreaks of melamine poisoning have occurred in both animals and humans during the past 7 years, which led to the identification of melamine and cyanuric acid as nephrotoxins. This Review provides an overview of the known experimental and observational data (including toxicology, epidemiology, and pathology) concerning melamine contamination of foodstuffs, both alone and in combination with cyanuric acid. The various renal effects of ingestion of these compounds in both animals and humans are described, and a hypothesis on the mechanism of formation of melamine-based kidney stones is presented. Finally, the public health measures taken in the wake of the melamine contamination events are discussed.
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Amelioration of renal ischemia-reperfusion injury with a novel protective cocktail.
J. Urol.
PUBLISHED: 02-25-2011
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Extended warm ischemia during partial nephrectomy can lead to considerable renal injury. Using a rat model of renal ischemia we examined the ability of a unique renoprotective cocktail to ameliorate warm ischemia-reperfusion injury.
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Prevalence of contraindications and prescription of pharmacologic therapies for gout.
Am. J. Med.
PUBLISHED: 02-08-2011
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Patients with gout have comorbidities, but the impact of these comorbidities on treatment has not been studied.
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Transplant nephrectomy after allograft failure is associated with allosensitization.
Urology
PUBLISHED: 01-13-2011
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To evaluate the effect of transplant nephrectomy (TN) on the percentage of panel reactive antibody (%PRA) and donor-specific antibody (DSA) levels in patients with renal allograft failure.
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Have advances in extracorporeal removal techniques changed the indications for their use in poisonings?
Adv Chronic Kidney Dis
PUBLISHED: 01-13-2011
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During the past 25 years, numerous changes have taken place in the use of hemodialysis as a therapeutic modality. Advances in technologies and a progression in our collective understanding of the pharmacokinetics of certain xenobiotics have resulted in alterations in the indications, effectiveness, and safety of hemodialysis. However, these changes have not necessarily been reflected in the current published data regarding treatment of intoxications. Reported clearance rates often reflect what was achievable in the 1970s and 1980s, and more recent reports are frequently lacking. Our goal in this review is to summarize the changes in hemodialysis and in other extracorporeal removal technologies and highlight the effects of these changes on the current indications for hemodialysis of the poisoned patient. Changes in dialysis performance that are reviewed in this article include the use of high-efficiency and high-flux dialysis membranes, improved hemodynamic stability because of ultrafiltration control, and the use of bicarbonate as a source of base. We review the indications for hemodialysis for removal of specific toxins, including vancomycin, methotrexate, carbamazepine, and valproic acid.
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Enhancing time-suspension sequences for the measurement of weak perturbations.
J. Magn. Reson.
PUBLISHED: 01-08-2011
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We detail key features for implementation of time-suspension multiple-pulse line-narrowing sequences. This sequence class is designed to null the average Hamiltonian (H¯(?)) over the period of the multiple-pulse cycle, typically to provide for high-resolution isolation of evolution from a switched interaction, such as field gradients for imaging or small sample perturbations. Sequence designs to further ensure null contributions from correction terms (H¯((¹)) and H¯(²)) of the Magnus expansion are also well known, as are a variety of approaches to second averaging, the process by which diagonal content is incorporated in H¯(?) to truncate unwanted terms. In spite of such designs, we observed spin evolution not explicable by H¯(?) using 16-, 24- and 48-pulse time-suspension sequences. We found three approaches to effectively remove artifacts that included splitting of the lineshape into unexpected multiplets as well as chirped evolution. The noted approaches are simultaneously compatible for combination of their benefits. The first ensures constant power deposition from RF excitation as the evolution period is incremented. This removes chirping and allows more effective 2nd averaging. Two schemes for the latter are evaluated: the noted introduction of a diagonal term in H¯(?), and phase-stepping the line-narrowing sequence on successive instances during the evolution period. Either of these was sufficient to remove artifactual splittings and to further enhance resolution, while in combination enhancements were maintained. Finally, numerical simulations provide evidence that our experimental line-narrowing results with ??As in crystalline GaAs approach performance limits of idealized sequences (e.g., with ideal square pulses, etc.). The three noted experimental techniques should likewise benefit ultimate implementation with switched interactions and corresponding new error contributions, which place further demand on sequence performance.
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Glomerular filtration rate slopes have significantly improved among renal transplants in the United States.
Transplantation
PUBLISHED: 11-19-2010
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In recent years, the use of higher risk donor organs and steroid avoidance regimens with potential increased acute rejection risk have increased. We hypothesized that these patterns adversely affect changes in posttransplant renal function.
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Gout and its comorbidities.
Bull NYU Hosp Jt Dis
PUBLISHED: 10-26-2010
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Gout is a chronic disease in which excessively high levels of serum urate (hyperuricemia) result in tissue depositions of sodium urate crystals and intermittent inflammatory attacks. Patients who have gout frequently experience a range of comorbidities, which complicates management and affects long-term prognosis. We review some of the more important of these comorbidities and consider the extent to which gout or hyperuricemia may be either a consequence or a cause of these related conditions. In addition, we briefly consider several neurological conditions in which the presence of gout or a high serum urate level may be associated with less disease, rather than more.
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Crystal growth inhibitors for the prevention of L-cystine kidney stones through molecular design.
Science
PUBLISHED: 10-16-2010
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Crystallization of L-cystine is a critical step in the pathogenesis of cystine kidney stones. Treatments for this disease are somewhat effective but often lead to adverse side effects. Real-time in situ atomic force microscopy (AFM) reveals that L-cystine dimethylester (L-CDME) and L-cystine methylester (L-CME) dramatically reduce the growth velocity of the six symmetry-equivalent {100} steps because of specific binding at the crystal surface, which frustrates the attachment of L-cystine molecules. L-CDME and L-CME produce l-cystine crystals with different habits that reveal distinct binding modes at the crystal surfaces. The AFM observations are mirrored by reduced crystal yield and crystal size in the presence of L-CDME and L-CME, collectively suggesting a new pathway to the prevention of L-cystine stones by rational design of crystal growth inhibitors.
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An emerging population: kidney transplant candidates who are placed on the waiting list after liver, heart, and lung transplantation.
Clin J Am Soc Nephrol
PUBLISHED: 09-02-2010
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ESRD has an adverse impact on patients who have had previous nonrenal solid-organ transplants (NRTxs; liver, heart, lung) and may be referred for a kidney transplant (KTx).
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Diet, but not oral probiotics, effectively reduces urinary oxalate excretion and calcium oxalate supersaturation.
Kidney Int.
PUBLISHED: 08-25-2010
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We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.
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Hidden selection bias deriving from donor organ characteristics does not affect performance evaluations of kidney transplant centers.
Med Care
PUBLISHED: 08-25-2010
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Transplant center performance evaluations have garnered substantial attention in recent years. Among sources of bias that may affect measured performance are underlying characteristics of donor organs. An unresolved question is whether centers accepting higher-risk donations are placed in jeopardy for lower evaluations independent of actual quality of care.
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Progressive renal papillary calcification and ureteral stone formation in mice deficient for Tamm-Horsfall protein.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 06-30-2010
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Mammalian urine contains a range of macromolecule proteins that play critical roles in renal stone formation, among which Tamm-Horsfall protein (THP) is by far the most abundant. While THP is a potent inhibitor of crystal aggregation in vitro and its ablation in vivo predisposes one of the two existing mouse models to spontaneous intrarenal calcium crystallization, key controversies remain regarding the role of THP in nephrolithiasis. By carrying out a long-range follow-up of more than 250 THP-null mice and their wild-type controls, we demonstrate here that renal calcification is a highly consistent phenotype of the THP-null mice that is age and partially gene dosage dependent, but is gender and genetic background independent. Renal calcification in THP-null mice is progressive, and by 15 mo over 85% of all the THP-null mice develop spontaneous intrarenal crystals. The crystals consist primarily of calcium phosphate in the form of hydroxyapatite, are located more frequently in the interstitial space of the renal papillae than intratubularly, particularly in older animals, and lack accompanying inflammatory cell infiltration. The interstitial deposits of hydroxyapatite observed in THP-null mice bear strong resemblances to the renal crystals found in human kidneys bearing idiopathic calcium oxalate stones. Compared with 24-h urine from the wild-type mice, that of THP-null mice is supersaturated with brushite (calcium phosphate), a stone precursor, and has reduced urinary excretion of citrate, a stone inhibitor. While less frequent than renal calcinosis, renal pelvic and ureteral stones and hydronephrosis occur in the aged THP-null mice. These results provide direct in vivo evidence indicating that normal THP plays an important role in defending the urinary system against calcification and suggest that reduced expression and/or decreased function of THP could contribute to nephrolithiasis.
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Pilot study of probiotic dietary supplementation for promoting healthy kidney function in patients with chronic kidney disease.
Adv Ther
PUBLISHED: 06-14-2010
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Uremic syndrome consists of nitrogenous waste retention, deficiency in kidney-derived hormones, and reduced acid excretion, and, if untreated, may progress to coma and eventual death. Previous experience suggests that oral administration of a probiotic formulation of selected microbial strains may extend renoprotection via intraintestinal extraction of toxic waste solutes in patients with chronic kidney disease (CKD)stages 3 and 4. This report presents preliminary data from a pilot study.
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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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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.