Ensemble-Based Assimilation of Satellite All-Sky Microwave Radiances Improves Intensity and Rainfall Predictions for Hurricane Harvey (2017).

Ensemble-based data assimilation of radar observations across inner-core regions of tropical cyclones (TCs) in tandem with satellite all-sky infrared (IR) radiances across the TC domain improves TC track and intensity forecasts. This study further investigates potential enhancements in TC track, intensity, and rainfall forecasts via assimilation of all-sky microwave (MW) radiances using Hurricane Harvey (2017) as an example. Assimilating Global Precipitation Measurement constellation all-sky MW radiances in addition to GOES-16 all-sky IR radiances reduces the forecast errors in the TC track, rapid intensification (RI), and peak intensity compared to assimilating all-sky IR radiances alone, including a 24-hr increase in forecast lead-time for RI. Assimilating all-sky MW radiances also improves Harvey's hydrometeor fields, which leads to improved forecasts of rainfall after Harvey's landfall. This study indicates that avenues exist for producing more accurate forecasts for TCs using available yet underutilized data, leading to better warnings of and preparedness for TC-associated hazards in the future.

Vascular smooth muscle cell durotaxis depends on extracellular matrix composition.

Mechanical compliance has been demonstrated to be a key determinant of cell behavior, directing processes such as spreading, migration, and differentiation. Durotaxis, directional migration from softer to more stiff regions of a substrate, has been observed for a variety of cell types. Recent stiffness mapping experiments have shown that local changes in tissue stiffness in disease are often accompanied by an altered ECM composition in vivo. However, the importance of ECM composition in durotaxis has not yet been explored. To address this question, we have developed and characterized a polyacrylamide hydrogel culture platform featuring highly tunable gradients in mechanical stiffness. This feature, together with the ability to control ECM composition, allows us to isolate the effects of mechanical and biological signals on cell migratory behavior. Using this system, we have tracked vascular smooth muscle cell migration in vitro and quantitatively analyzed differences in cell migration as a function of ECM composition. Our results show that vascular smooth muscle cells undergo durotaxis on mechanical gradients coated with fibronectin but not on those coated with laminin. These findings indicate that the composition of the adhesion ligand is a critical determinant of a cell's migratory response to mechanical gradients.

Extracellular matrix type modulates cell migration on mechanical gradients.

Extracellular matrix composition and stiffness are known to be critical determinants of cell behavior, modulating processes including differentiation, traction generation, and migration. Recent studies have demonstrated that the ECM composition can modulate how cells migrate in response to gradients in environmental stiffness, altering a cell's ability to undergo durotaxis. These observations were limited to single varieties of extracellular matrix, but typically cells are exposed to environments containing complex mixtures of extracellular matrix proteins. Here, we investigate migration of NIH 3T3 fibroblasts on mechanical gradients coated with one or more type of extracellular matrix protein. Our results show that NIH 3T3 fibroblasts exhibit durotaxis on fibronectin-coated mechanical gradients but not on those coated with laminin, demonstrating that extracellular matrix type can act as a regulator of cell response to mechanical gradients. Interestingly, NIH 3T3 fibroblasts were also observed to migrate randomly on gradients coated with a mixture of both fibronectin and laminin, suggesting that there may be a complex interplay in the cellular response to mechanical gradients in the presence of multiple extracellular matrix signals. These findings indicate that specific composition of available adhesion ligands is a critical determinant of a cell's migratory response to mechanical gradients.

Ultrasonographic Assessment of Testicular Viability Using Heterogeneity Levels in Torsed Testicles.

PURPOSE: Gross testicular heterogeneity on ultrasound has been associated with testis loss following testicular torsion in children. We aimed to quantify the extent of temporal heterogeneity associated with testis loss in testicular torsion cases using a noninvasive technique to determine a HI (heterogeneity index) on ultrasound images. MATERIALS AND METHODS: We retrospectively studied the records of patients who presented with acute scrotal pain to the Pediatric Emergency Department over a 6-year period. Ultrasound images of the affected testis and the unaffected contralateral testis were examined using a proprietary program to determine the extent of heterogeneity of each image. The difference between the HI of the torsed testis and that of the contralateral normal testis was termed ΔHI. Receiver operating characteristics curve analysis was performed to determine the ΔHI threshold for nonviability. RESULTS: Among 529 patients who presented with acute scrotal pain 147 had testicular torsion based on surgical findings. Of these 147 patients 110 (74.8%) were found to have a viable testis while 37 (25.2%) had a nonviable testis. Using the ΔHI cutoff of 0.394 or greater for nonviability, sensitivity and specificity were 100% and 94.5%, respectively. Positive and negative predictive values were 86% and 100%, respectively. CONCLUSIONS: Our results demonstrate that a quantifiable temporal gradation of heterogeneity exists and the heterogeneity index can be used as an objective parameter to determine the viability of a torsed testicle. By developing the technology to measure the heterogeneity index in real time, we could potentially identify which patients with testicular torsion have a nonviable testicle and, thus, would not require immediate surgical exploration.

Differences in 24-h urine composition between nephrolithiasis patients with and without diabetes mellitus.

OBJECTIVES: To examine the differences in 24-h urine composition between nephrolithiasis patients with and without diabetes mellitus (DM) in a large cohort of stone-formers and to examine differences in stone composition between patients with and without DM. PATIENTS AND METHODS: A retrospective review of 1117 patients with nephrolithiasis and a 24-h urine analysis was completed. Univariable analysis of 24-h urine profiles and multivariable linear regression models were performed, comparing patients with and without DM. A subanalysis of patients with stone analysis data available was performed, comparing the stone composition of patients with and without DM. RESULTS: Of the 1117 patients who comprised the study population, 181 (16%) had DM and 936 (84%) did not have DM at the time of urine analysis. Univariable analysis showed significantly higher total urine volume, citrate, uric acid (UA), sodium, potassium, sulphate, oxalate, chloride, and supersaturation (SS) of UA in individuals with DM (all P < 0.05). However, patients with DM had significantly lower SS of calcium phosphate and pH (all P < 0.05). Multivariable analysis showed that patients with DM had significantly lower urinary pH and SS of calcium phosphate, but significantly greater citrate, UA, sulphate, oxalate, chloride, SSUA, SS of calcium oxalate, and volume than patients without DM (all P < 0.05). Patients with DM had a significantly greater proportion of UA in their stones than patients without DM (50.2% vs 13.5%, P < 0.001). CONCLUSIONS: DM was associated with multiple differences on 24-h urine analysis compared with those without DM, including significantly higher UA and oxalate, and lower pH. Control of urinary UA and pH, as well as limiting intake of dietary oxalate may reduce stone formation in patients with DM.

Association of serum biochemical metabolic panel with stone composition.

INTRODUCTION: To determine the association of the basic metabolic panel with stone type. METHODS: The present study was a retrospective review of 492 stone formers with both stone composition analysis and basic metabolic panel available. Analysis of a basic metabolic panel across stone types was carried out using Fisher's exact test and analysis of variance. Multinomial logistic regression was used to predict stone type based on a basic metabolic panel. RESULTS: A total of 272 (55%) patients had predominantly calcium oxalate stones, 100 (21%) had uric acid stones, 93 (19%) had calcium phosphate stones, 16 (3%) had mixed stones and 11 (2%) had other types of stones. Uric acid stone formers had the highest serum glucose, blood urea nitrogen and creatinine levels. Calcium oxalate stone formers had the highest serum sodium. No significant differences in mean serum calcium levels across different stone types were identified. The predicted risk of uric acid stone over the other stone types increased with an increase in serum glucose and decreased with an increase in carbon dioxide levels. The predicted risk of calcium oxalate stones increased with an increase in serum sodium and chloride levels. The predicted risk of calcium phosphate and oxalate stones over the other stone types increased with an increase in serum calcium levels. The overall accuracy of the basic metabolic panel alone to predict stone type was 59%. CONCLUSION: A basic metabolic panel alone or in combination with 24-h urinalysis and demographics does not accurately predict stone type. However, it can be used in combination with other variables to predict stone composition.

Using 24-hour urinalysis to predict stone type.

PURPOSE: We determined the accuracy of 24-hour urinalysis in predicting stone type and identify the associations between 24-hour urine elements with stone type. MATERIALS AND METHODS: We performed a retrospective review of 503 stone formers with stone composition analysis and 24-hour urinalysis available. Analysis of 24-hour urine elements across stone types was performed using Fisher's exact test and ANOVA. Multinomial logistic regression was used to predict stone type based on 24-hour urinalysis. RESULTS: A total of 280 (56%) patients had predominantly calcium oxalate, 103 (20%) had uric acid, 93 (19%) had calcium phosphate, 16 (3%) had mixed and 11 (2%) had other stone types. There were several significant patient characteristics and 24-hour urinalysis differences across stone type groups. The statistical model predicted 371 (74%) calcium oxalate, 78 (16%) uric acid, 52 (10%) calcium phosphate, zero mixed and 2 (less than 1%) other stone types. The model correctly predicted calcium oxalate stones in 85%, uric acid in 51%, calcium phosphate in 31%, mixed in 0% and other stone types in 18% of the cases. Of the predicted stone types, correct predictions were 61%, 69%, 56% and 71% for calcium oxalate, uric acid, calcium phosphate and other stones types, respectively. The overall accuracy was 64%. Plots were used to explore the associations between each 24-hour urine element with each predicted stone type adjusted for all the others urinary elements. CONCLUSIONS: A 24-hour urinalysis alone does not accurately predict stone type. However, it may be used in conjunction with other variables to predict stone composition.

Prospective Randomized Trial of Antibiotic Prophylaxis Duration for Percutaneous Nephrolithotomy in Low-Risk Patients.

Introduction and Objective: Postoperative infection and sepsis account for the most common complications following percutaneous nephrolithotomy (PCNL), as high as 14% in low-risk patients. Although the American Urological Association (AUA) recommends perioperative antibiotics for 24 hours or less for PCNL, practice patterns vary regarding duration of antibiotic therapy. We aimed to compare the efficacy of 24-hour antibiotic coverage vs short-course protocol of antibiotic prophylaxis for PCNL. Materials and Methods: Low-risk patients with a sterile preoperative urine culture undergoing PCNL were prospectively randomized to antibiotics for up to 24 hours after procedure (24Hr) or continued until external urinary catheters were removed (CR) study groups. Patients were given a first generation cephalosporin, or ciprofloxacin in patients with penicillin allergy. Exclusion criteria included age <18 years, receiving antibiotics immediately before the procedure, history of urosepsis, presence of indwelling catheter >1 week, multistage procedure, immunosuppression, pregnancy, multiple antibiotic allergies, and patients who are breastfeeding. Results: Ninety-eight patients were randomized to either 24Hr (n = 49) or CR (n = 49). Mean duration of antibiotic administration was 20.6 and 34.0 hours in the 24Hr and CR groups (p = 0.04), respectively. Age, comorbidities, stone size, operative time, number of punctures, dilations, and proportion of "tubeless" procedures were similar between groups. There were no differences in febrile episodes, rates of systemic inflammatory response syndrome, bacteremia, or culture-proven postoperative urinary tract infection between the 24Hr and CR groups. Overall complication rates were similar between groups. In a subgroup analysis which excluded "tubeless" patients (24 and 29 patients in 24Hr and CR groups, respectively), no differences were seen in postoperative outcomes. Conclusions: In a randomized, prospective study, we found that a 24-hour protocol for antibiotic prophylaxis is not associated with increased risk of infection-related events compared to giving antibiotics until external catheters are removed in patients with low infectious risk undergoing PCNL. Clinicaltrials.gov: NCT02579161.

Presentation of bladder leiomyoma concurrent with transitional cell carcinoma.

We report a case of a 46-year-old male who presented to the outpatient urology clinic with an incidental bladder mass. Office cystoscopy revealed two synchronous tumors of different morphology. Endoscopic resection was performed to remove the smaller, papillary tumor, of which pathology revealed Ta, Grade 1 urothelial carcinoma. A second open resection was performed to remove the second tumor, a benign leiomyoma.

A Ca2+-dependent bacterial antifreeze protein domain has a novel beta-helical ice-binding fold.

AFPs (antifreeze proteins) are produced by many organisms that inhabit ice-laden environments. They facilitate survival at sub-zero temperatures by binding to, and inhibiting, the growth of ice crystals in solution. The Antarctic bacterium Marinomonas primoryensis produces an exceptionally large(>1 MDa) hyperactive Ca2+-dependent AFP. We have cloned,expressed and characterized a 322-amino-acid region of the protein where the antifreeze activity is localized that shows similarity to the RTX (repeats-in-toxin) family of proteins. The recombinant protein requires Ca2+ for structure and activity, and it is capable of depressing the freezing point of a solution in excess of 2 degrees C at a concentration of 0.5 mg/ml, therefore classifying it as a hyperactive AFP. We have developed a homology-guided model of the antifreeze region based partly on the Ca2+-bound beta-roll from alkaline protease. The model has identified both a novel beta-helical fold and an ice-binding site. The interior of the beta-helix contains a single row of bound Ca2+ ions down one side of the structure and a hydrophobic core down the opposite side. The ice binding surface consists of parallel repetitive arrays of threonine and aspartic acid/asparagine residues located down the Ca2+-bound side of the structure. The model was tested and validated by site-directed mutagenesis. It explains the Ca2+-dependency of the region, as well its hyperactive antifreeze activity. This is the first bacterial AFP to be structurally characterized and is one of only five hyperactive AFPs identified to date.AFPS

Renal functional outcomes are not adversely affected by selective angioembolization following percutaneous nephrolithotomy.

OBJECTIVE: Selective angioembolization (SAE) effectively diagnoses and treats iatrogenic vascular complications following percutaneous nephrolithotomy (PCNL). METHODS: We retrospectively reviewed 1329 consecutive PCNLs and identified patients who underwent SAE following PCNL with at least 12-month follow-up. Estimated glomerular filtration rate (eGFR) was calculated for all patients preoperatively, postoperatively and at last follow-up. A 1:2 matched cohort analysis was performed. RESULTS: Twenty-three patients underwent SAE and matched to 46 controls. There was no statistically significant difference in preoperative, postoperative, and follow-up eGFR when comparing patients who underwent SAE and those with an uneventful course. CONCLUSION: Long-term eGFR is comparable in patients who undergo uncomplicated PCNL and those requiring SAE.

Robotic Partial Nephrectomy: The Will Rogers Surgical Effect.

Comparison of surgical techniques must be critically and objectively evaluated, ideally in the context of prospective trials. Comprehensive surgical training ensures that patients are offered the most appropriate treatment and highest clinical care.

Nasal Septal Deviation and Facial Skeletal Asymmetries.

During ontogeny, the nasal septum exerts a morphogenetic influence on the surrounding facial skeleton. While the influence of the septum is well established in long snouted animal models, its role in human facial growth is less clear. If the septum is a facial growth center in humans, we would predict that deviated septal growth would be associated with facial skeletal asymmetries. Using computed tomographic (CT) scans of n = 55 adult subjects, the purpose of this study was to test whether there is a correlation between septal deviation and facial asymmetries using three-dimensional (3D) geometric morphometric techniques. We calculated deviation as a percentage of septal volume relative to the volume of a modeled non-deviated septum. We then recorded skeletal landmarks representing the nasal, palatal, and lateral facial regions. Landmark data were superimposed using Procrustes analysis. First, we examined the correlation between nasal septal deviation and the overall magnitude of asymmetry. Next, we assessed whether there was a relationship between nasal septal deviation and more localized aspects of asymmetry using multivariate regression analysis. Our results indicate that while there was no correlation between septal deviation and the overall magnitude of asymmetry, septal deviation was associated with asymmetry primarily in the nasal floor and the palatal region. Septal deviation was unassociated with asymmetries in the lateral facial skeleton. Though we did not test the causal relationship between nasal septal deviation and facial asymmetry, our results suggest that the nasal septum may have an influence on patterns of adult facial form.

Association of estimated glomerular filtration rate with 24-h urinalysis and stone composition.

The aim of this study is to determine the association of estimated glomerular filtration rate (eGFR) with 24-h urine analysis and stone composition. We performed a retrospective review of 1060 stone formers with 24-h urinalysis, of which 499 had stone composition analysis available. Comparisons of baseline patient characteristics and urinary abnormalities across eGFR groups (<60, 60-89.9, ≥90 mL/min/1.73 m(2)) were performed using Fisher's exact test for categorical data and analysis of variance for continuous variables. Analyses of 24-h urinalysis and stone composition across eGFR groups were performed using linear regression with eGFR groups as a continuous variable to evaluate trends. Of the 1060 patients in the study, 595 (56 %) were males. The mean age was 53.8 years. A total of 38 (4 %), 77 (7 %), and 945 (89 %) patients had eGFR <60, 60-89.9, and ≥90 mL/min/1.73 m(2), respectively. Lower eGFR was associated with older age, lower body-mass index, and female gender (all P < 0.05). Lower eGFR was also associated with lower urinary volume, calcium, citrate, uric acid, sodium, magnesium, phosphorus, sulfate, and creatinine on both univariable and multivariable analyses, adjusted for demographics, comorbidities and medication use (all P < 0.05). The prevalence of hypocitraturia and hypomagnesuria was associated with decreased eGFR, while hypercalciuria, hyperoxaluria, hyperuricosuria and hyperphosphaturia were associated with higher eGFR (all P < 0.05). Stone composition was similar across eGFR groups (all P > 0.05). In conclusion, lower eGFR was associated with lower excretion of urinary elements in a routine 24-h urinalysis, but similar stone composition.

Surgical Complications and Their Repercussions.

PURPOSE: Surgical complications have a significant impact on intended quality of care. The aim of our study was to identify factors that contribute to the propagation of additional postoperative complications. MATERIALS AND METHODS: Over a 1-year period, we prospectively identified and retrospectively reviewed data on all patients who experienced a surgical complication within 30 days of their procedure. A complication was defined as any deviation from the expected postoperative course and was described using the Clavien-Dindo classification. Data reviewed included length of stay (LOS), Clavien grade, readmission status, and management of the complication. Surgeries were stratified into retroperitoneal, pelvic, and endoscopic procedures. The association between complications and Clavien grade was measured using Spearman rank-order correlation. The probability of subsequent complications and readmission was measured using exact logistic regression. RESULTS: Of the 4414 patients who underwent a urologic procedure, 191 (4.3%) had at least one complication. One hundred thirty-four (70%) of these patients had more than one complication, 84 (44%) had more than three complications, and 12 (6.3%) had up to a seventh complication. LOS was affected by the severity of the initial complication. Patients with initial Clavien grades 1, 2, 3a, 3b, and 4 had an LOS of 3.75, 4.17, 4.21, 4.94, and 8.58 days, respectively. Variables associated with the risk of developing a second complication included diabetes mellitus, longer operative times (OR 1.83), and greater estimated blood loss (OR 1.32). CONCLUSIONS: Surgical patients with an initial complication are at higher risk for multiple subsequent postoperative complications. Complications are associated with an extended LOS and higher readmission rates. Diabetes, longer operative time, and greater blood loss were identified as risk factors for multiple complications.

Bladder ganglioneuroma in a 5-year-old girl presenting with a urinary tract infection and hematuria: case report and review of the literature.

Ganglioneuromas are rare benign tumors arising from neural crest cells of the autonomic nervous system. These tumors may rarely localize to the bladder, and few cases have been reported in the adult literature. To date, however, bladder ganglioneuromas have not been reported in the pediatric literature. We report the case of a 5-year-old girl who presented with hematuria and a urinary tract infection and on workup was found to have a large bladder mass. Transurethral resection and pathologic examination revealed the mass to be a ganglioneuroma. The case is presented followed by a brief review of the literature.

Advances in percutaneous stone surgery.

Treatment of large renal stones has changed considerably in recent years. The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before, and this has been met with improvements in percutaneous stone surgery. In this review paper, we examine recent developments in percutaneous stone surgery, including advances in diagnosis and preoperative planning, renal access, patient position, tract dilation, nephroscopes, lithotripsy, exit strategies, and post-operative antibiotic prophylaxis.

Does hypertension impact 24-hour urine parameters in patients with nephrolithiasis?

OBJECTIVE: To examine the differences in 24-hour urine parameters and stone composition between patients with and without systemic hypertension (HTN) in a large cohort of stone formers. MATERIALS AND METHODS: We performed a retrospective review over a 10-year period of patients with stone, who had completed a 24-hour urinalysis (Litholink) and for whom demographic information was available, including the presence of HTN. Univariate and multivariate analyses were performed, comparing the 24-hour urinalysis profiles of patients with HTN with that of normotensive patients. RESULTS: Of the 1115 patients eligible for inclusion, 442 patients (40%) had HTN and 673 (60%) did not. Patients with HTN were significantly older, had a higher body mass index, and had a greater number of comorbid conditions than normotensive patients. Univariate analysis revealed significantly lower urine pH, calcium, supersaturation (SS) of calcium oxalate (CaOx) and SS calcium phosphate (all P <.05) in patients with HTN. Multivariate analysis showed significantly lower calcium, citrate, and SS CaOx in patients with HTN (all P <.05). CONCLUSION: Our results demonstrate lower levels of calcium and SS CaOx on univariate and multivariate analysis, as well as lower levels of citrate on multivariate analysis in patients with HTN. These results suggest that lower levels of citrate may contribute to stone formation to a greater degree in patients with HTN than abnormalities in calcium metabolism.

Age-related changes in 24-hour urine composition must be considered in the medical management of nephrolithiasis.

BACKGROUND AND PURPOSE: Over the past 50 years, there has been an upward shift in the age of peak incidence of stone disease, yet less is known regarding how the urinary biochemical profile changes with aging. Therefore, we sought to examine the relationship between age and 24-hour urine composition. METHODS: We retrospectively reviewed a database of our tertiary care stone clinic patients seen from March 2002 to February 2012. Analysis of pretreatment 24-hour urine collections across age groups was performed using univariate analysis of variance and multivariate linear regression models adjusting for clinical and demographic factors and 24-hour urine parameters. RESULTS: A total of 1115 patients were broken down into age groups consisting of <45 years (221; 19.7%), 45-54.9 years (270; 23.8%), 55-64.9 years (270; 24.6%), and ≥65 years (356; 31.9%). Univariate analysis found significant ascending trends with aging for mean body mass index, while mean urine pH, 24-hour calcium, uric acid (UA), ammonium, creatinine, and supersaturation (SS) of calcium oxalate (CaOx) and calcium phosphate (CaP) decreased with age (all P for trend <0.05). Adjusted multivariate analysis demonstrated that increased age was significantly associated with increased 24-hour citrate and SS UA, whereas increased age was significantly associated with decreased pH, 24-hour UA, creatinine, SS CaOx, and SS CaP (all P for trend <0.05). CONCLUSIONS: There are numerous age-related changes in the metabolic profile as seen on 24-hour urine collection. This highlights the importance of evaluating stone-forming patients of all ages with 24-hour urine collections because both the type and degree of metabolic abnormality may change with age.

Comparison of the metabolic profile of mixed calcium oxalate/uric acid stone formers to that of pure calcium oxalate and pure uric acid stone formers.

OBJECTIVE: To compare the metabolic profile of patients who form mixed calcium oxalate (CaOx)/uric acid (UA) stones to those of pure CaOx and pure UA stone formers. METHODS: We performed a retrospective review of 232 patients, with both stone composition analysis and 24-hour urine collection, seen between March 2002 and April 2012. Analysis of 24-hour urine constituents across the 3 stone groups (pure UA, pure CaOx, and mixed CaOx/UA) was performed using univariate analysis of variance and multivariate linear regression models adjusting for clinical and demographic factors and 24-hour urine collection elements. RESULTS: A total of 27 patients (11.6%) had mixed CaOx/UA, 122 (52.6%) had pure CaOx, and 83 (35.8%) had pure UA calculi. Univariate analysis demonstrated significant differences between mixed CaOx/UA patients and pure CaOx patients for urine pH (mixed, 5.63 ± 0.49 vs pure, CaOx 5.93 ± 0.51; P = .009) and supersaturation (SS) UA (mixed, 1.84 ± 1.09 vs pure, CaOx 1.26 ± 0.93; P = .01), and a significant difference between mixed CaOx/UA patients and pure UA patients for SS CaOx (mixed, 7.18 ± 4.23 vs pure, UA 4.90 ± 2.96; P = .005). Multivariate analysis demonstrated that mixed CaOx/UA patients had no significant difference in SS CaOx as compared with pure CaOx patients (difference, -0.27; P = .66), whereas at the same time had no significant difference in SS UA as compared with pure UA patients (-0.07; P = .69). CONCLUSION: The metabolic profile of patients who form mixed CaOx/UA stones demonstrates abnormalities that promote both CaOx and UA stone formation. Dietary and medical management for this group of patients should address treatment of both defects.