Faculty Bibliography

Background: Potassium citrate is a mainstay of treatment to prevent calcium stones. However, it can increase urine pH and calcium phosphate (CaP) supersaturation (SS). HCA, extracted from garcinia cambogia, is a potent inhibitor of calcium oxalate (CaOx) crystal growth in vitro and may not yield HCO3. It is "generally regarded as safe" and available over the counter. We studied how HCA supplementation affects urine chemistry.
Method(s): We enrolled 2 groups: calcium stone formers (SF) and non-stone forming (NSF) controls. Thiazides and potassium citrate were held for 2 weeks prior to study. Participants recorded a self-selected diet for 2 days and performed 24-hour urine collection on day 2. HCA 300 mg 3 times daily was taken orally for 7 days, and 24-hour urine collected on day 7 while the patient replicated the initial, self-selected diet.
Result(s): 13 people, aged 26-76 years, participated. There were 6 SF and 7 NSF, combined into 1 group of 13. Patients replicated their diets well, as urine Na, volume, and creatinine were similar (data not shown). Results presented in Table. HCA increased urine K and citrate (P < 0.001 and 0.013 respectively). Mean urine pH was unchanged (6.25 to 6.47, P=0.14), while urinary NH4 fell (P = 0.017). 24h excretion of Ca and Ox did not change. SS of CaOx and CaP did not change. Serum values did not change: baseline HCO3 and K were 23.5 +/- 2.5 and 4.0 +/- 0.2 meq/L and 23.7 +/- 1.8 and 4.4 +/- 0.6 meq/L after HCA.
Conclusion(s): Urine K excretion rose by 29 meq/day compared with an expected increase based on the label of 14 meq, suggesting the label was not accurate. Increased citrate and lower NH4 suggest some K is in the form of alkali salts or that some HCA is metabolized to bicarbonate. There was no change in CaP or CaOx SS. The lack of effect on SS may not reflect the potential ability of HCA to inhibit calcium crystallization, as it inhibits Ca crystal growth in vitro in supersaturated media

OBJECTIVE:To evaluate the quality and readability of online information on ureteral stents. METHODS:Google.com was queried using the search terms "ureteric stent", "ureteral stent", "double J stent" and, "Kidney stent" derived from Google AdWords. Website popularity was determined using Google Rank and the Alexa tool. Website quality assessment was performed using the following criteria: Journal of the American Medical Association (JAMA) benchmarks, Health on the Net (HON) criteria, and a customized DISCERN questionnaire. The customized DISCERN questionnaire was developed by combining the short validated DISCERN questionnaire with additional stent-specific items including definition, placement, complications, limitations, removal and "when to seek help". Scores related to stent items were considered as the "stent score" (SS). Readability was evaluated using five readability tests. RESULTS:Thirty-two websites were included. The mean customized DISCERN score and "stent score" were 27.1 ± 7.1 (maximum possible score = 59) and 14.6 ± 3.8 (maximum possible score = 24), respectively. A minority of websites adequately addressed "stent removal" and "when to seek medical attention". Only two websites (6.3%) had HON certification (drugs.com, radiologyinfo.org) and only one website (3.3%) met all JAMA criteria (bradyurology.blogspot.com). Readability level was higher than the American Medical Association recommendation of sixth-grade level for more than 75% of the websites. There was no correlation between Google rank, Alexa rank, and the quality scores (P > 0.05). DISCUSSION/CONCLUSIONS:Among the 32 most popular websites on the topic of ureteral stents, online information was highly variable. The readability of many of the websites was far higher than standard recommendations and the online information was questionable in many cases. These findings suggest a need for improved online resources in order to better educate patients about ureteral stents and also should inform physicians that popular websites may have incomplete information.

OBJECTIVE: To determine whether patient-specific 3D printed renal tumor models change pre-operative planning decisions made by urological surgeons in preparation for complex renal mass surgical procedures. MATERIALS AND METHODS: From our ongoing IRB approved study on renal neoplasms, ten renal mass cases were retrospectively selected based on Nephrometry Score greater than 5 (range 6-10). A 3D post-contrast fat-suppressed gradient-echo T1-weighted sequence was used to generate 3D printed models. The cases were evaluated by three experienced urologic oncology surgeons in a randomized fashion using (1) imaging data on PACS alone and (2) 3D printed model in addition to the imaging data. A questionnaire regarding surgical approach and planning was administered. The presumed pre-operative approaches with and without the model were compared. Any change between the presumed approaches and the actual surgical intervention was recorded. RESULTS: There was a change in planned approach with the 3D printed model for all ten cases with the largest impact seen regarding decisions on transperitoneal or retroperitoneal approach and clamping, with changes seen in 30%-50% of cases. Mean parenchymal volume loss for the operated kidney was 21.4%. Volume losses >20% were associated with increased ischemia times and surgeons tended to report a different approach with the use of the 3D model compared to that with imaging alone in these cases. The 3D printed models helped increase confidence regarding the chosen operative procedure in all cases. CONCLUSIONS: Pre-operative physical 3D models created from MRI data may influence surgical planning for complex kidney cancer.

Purpose Pre-operative three-dimensional (3D) printed renal malignancy models are tools with potential benefits in surgical training and patient education [1,2]. Most importantly, 3D models may facilitate surgical planning by allowing surgeons to assess tumor complexity as well as the relationship of the tumor to major anatomic structures [3]. The objective of this study was to evaluate this impact. Methods Imaging was obtained from an IRB approved, prospectively collected database of multiparametric magnetic resonance imaging (MRI) of renal masses. Ten cases eligible for elective partial nephrectomy were retrospectively selected. High-fidelity models were 3D printed in multiple colors based on T1 images (Fig. 1). Cases were reviewed by three attending surgeons and six senior residents with imaging alone and in addition to the 3D model. A standardized questionnaire was developed to capture the planned surgical approach and intraoperative technique in both sessions. Results Surgical approach was changed in 20 % of decisions, intraoperative considerations were changed in 40 % (Fig. 2). Thirty percent and 23 % of decisions in the attending and resident groups, respectively, were altered by the 3D model. Overall, every case was modified with this additional information. All participants reported that the models helped plan the surgical approach for partial nephrectomy. Most reported improved comprehension of anatomy and confidence in surgical plan. Half reported that the 3D printed model altered their surgical plan significantly. Due to use of T1 images, reconstruction of calyces and tertiary blood vessels were limited: 8 of the 9 participants desired more information regarding these structures. (Figure presented) Conclusion Utilization of 3D modeling may aid in pre-operative and intra-operative planning for both attending and resident surgeons. While 3D models with MR imaging is feasible, computed tomography (CT) imaging may provide additional anatomical information. Future study is required to prospectively assess the utility of models and pre-operative planning and intra-operative guidance

We describe flexible ureteroscopy-directed retrograde nephrostomy access using a puncture wire to achieve renal access. This is a natural extension of modern retrograde intrarenal surgical techniques and a modernization of the original Lawson technique for retrograde nephrostomy tract creation. In appropriately selected patients, this approach is safe and permits reduced radiation exposure. We believe this technique is easy to learn and may overcome the difficult learning curve of antegrade nephrostomy techniques faced by urologists who have not undergone subspecialty training in endourology.

We previously reported that miR-1 is among the most consistently down-regulated miRs in primary human prostate tumors. In this follow-up study, we further corroborated this finding in an independent data set and made the novel observation that miR-1 expression is further reduced in distant metastasis and is a candidate predictor of disease recurrence. Moreover, we performed in vitro experiments to explore the tumor suppressor function of miR-1. Cell-based assays showed that miR-1 is epigenetically silenced in human prostate cancer. Overexpression of miR-1 in these cells led to growth inhibition and down-regulation of genes in pathways regulating cell cycle progression, mitosis, DNA replication/repair and actin dynamics. This observation was further corroborated with protein expression analysis and 3'-UTR-based reporter assays, indicating that genes in these pathways are either direct or indirect targets of miR-1. A gene set enrichment analysis revealed that the miR-1-mediated tumor suppressor effects are globally similar to those of histone deacetylase inhibitors. Lastly, we obtained preliminary evidence that miR-1 alters the cellular organization of F-actin and inhibits tumor cell invasion and filipodia formation. In conclusion, our findings indicate that miR-1 acts as a tumor suppressor in prostate cancer by influencing multiple cancer-related processes and by inhibiting cell proliferation and motility.