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Objectives: To study the long-term outcomes of the flexible and navigable suction ureteral access sheath (FANS) in flexible ureteroscopy (FURS). FANS has well-established efficiency and 30-day perioperative safety; however, its influence on pelvicalyceal and ureteric anatomy remains to be investigated., Methods: This was a prospective study of patients with normal renal anatomy who underwent FURS with FANS for renal stones from April 2023 to August 2024 in 16 centers worldwide. 30-day postoperative stone free rate and delayed complications after 3 months were analyzed with a non-contrast CT scan and contrasted CT urogram respectively. The primary aim was to report if FANS could potentially cause pelviureteric junction, pelvicalyceal or ureteric complications., Results: 310 patients were analyzed. Median age was 51; median stone volume was 1584 mm 3 . Disposable scopes were used in 58.1%. Predominant laser energies were Thulium fiber laser (56.1%) followed by Thulium-YAG laser (20.6%). Median laser time was 14min, median ureteroscopy time was 30min, and median total operation time was 45min. Ureteric injury occurred in 11 patients (3.5%), of which 10 were Traxer-Thomas Grade 1. On 30-day NCCT, 63.5% of patients had zero residual fragments; overall stone-free status was seen in 95.1%. 30-day reintervention rate was 4.2% (13 cases). 3-month CT urogram showed ureteric stenosis in only 1 patient (0.3%) who was managed by dilatation and stenting. No other anatomical anomalies were recorded., Conclusions: The extremely low rates of 3-month adverse outcomes, high immediate SFR, and low 30-day reintervention rates further strengthen the evidence for safety and effectiveness of FANS., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ben Turney is a consultant for Boston Scientific, EMS, and Pusen. The other authors have no COI to declare. CONFLICTS OF INTEREST Ben Turney is a consultant for Boston Scientific, EMS, and Pusen. The other authors have no COI to declare., (Copyright © 2025 Elsevier Inc. All rights reserved.)

Purpose of Review: Stress urinary incontinence is a growing issue in ageing men, often following treatment for prostate cancer or bladder outflow obstruction. While implantable urological devices offer relief, infections are a significant concern. These infections can lead to device removal, negating the benefits and impacting patient outcomes. This review explores the risks and factors contributing to these infections and existing strategies to minimize them. These strategies encompass a multifaceted approach that considers patient-specific issues, environmental issues, device design and surgical techniques. However, despite these interventions, there is still a pressing need for further advancements in device infection prevention., Recent Findings: Faster diagnostics, such as Raman spectroscopy, could enable early detection of infections. Additionally, biocompatible adjuncts like ultrasound-responsive microbubbles hold promise for enhanced drug delivery and biofilm disruption, particularly important as antibiotic resistance rises worldwide., Summary: By combining advancements in diagnostics, device design, and patient-specific surgical techniques, we can create a future where implantable urological devices offer men a significant improvement in quality of life with minimal infection risk., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To map current literature and provide an overview of upcoming future diagnostic and prognostic methods for upper tract urothelial carcinoma (UTUC), including translational medical science., Methods: A scoping review approach was applied to search the literature. Based on the published literature, and the experts own experience and opinions consensus was reached through discussions at the meeting Consultation on UTUC II in Stockholm, September 2022., Results: The gene mutational profile of UTUC correlates with stage, grade, prognosis, and response to different therapeutic strategies. Analysis of pathway proteins downstream of known pathogenic mutations might be an alternative approach. Liquid biopsies of cell-free DNA may detect UTUC with a higher sensitivity and specificity than urinary cytology. Extracellular vesicles from tumour cells can be detected in urine and may be used to identify the location of the urothelial carcinoma in the urinary tract. 3D microscopy of UTUC samples may add information in the analysis of tumour stage. Chemokines and chemokine receptors were linked to overall survival and responsiveness to neoadjuvant chemotherapy in muscle-invasive bladder cancer, which is potentially also of interest in UTUC., Conclusion: Current diagnostic methods for UTUC have shortcomings, especially concerning prognostication, which is important for personalized treatment decisions. There are several upcoming methods that may be of interest for UTUC. Most have been studied for urothelial carcinoma of the bladder, and it is important to keep in mind that UTUC is a different entity and not all methods are adaptable or applicable to UTUC., (© 2023. The Author(s).)

Different international associations have proposed their own guidelines on urolithiasis. However, the focus is primarily on an overview of the principles of urolithiasis management rather than step-by-step technical details for the procedure. The International Alliance of Urolithiasis (IAU) is releasing a series of guidelines on the management of urolithiasis. The current guideline on shockwave lithotripsy (SWL) is the third in the IAU guidelines series and provides a clinical framework for urologists and technicians performing SWL. A total of 49 recommendations are summarized and graded, covering the following aspects: indications and contraindications; preoperative patient evaluation; preoperative medication; prestenting; intraoperative analgesia or anesthesia; intraoperative position; stone localization and monitoring; machine and energy settings; intraoperative lithotripsy strategies; auxiliary therapy following SWL; evaluation of stone clearance; complications; and quality of life. The recommendations, tips, and tricks regarding SWL procedures summarized here provide important and necessary guidance for urologists along with technicians performing SWL. PATIENT SUMMARY: For kidney and urinary stones of less than 20 mm in size, shockwave lithotripsy (SWL) is an approach in which the stone is treated with shockwaves applied to the skin, without the need for surgery. Our recommendations on technical aspects of the procedure provide guidance for urologists and technicians performing SWL., (Copyright © 2022. Published by Elsevier B.V.)

We present preliminary stone ablation rate results from an automated bench model using two pulse-modulated Ho:YAG lasers and a thulium fibre laser (TFL) in contact and non-contact modes. Ablation rate was assessed using automated apparatus that moved the laser fibre across flat BegoStone phantoms at a constant stone-to-fibre working distance (WD). Pre-soaked and unsoaked stones were used. A range of powers (20-60 W) was tested at WD of up to 3 mm. In pseudocontact, the prototype Ho:YAG laser produced higher ablation than the reference Ho:YAG laser at all powers tested (p < 0.002), and higher ablation than TFL at 20 W and 40 W (p < 0.001). At distance, ablation rates for the prototype were higher than the reference Ho:YAG laser using pre-soaked stones at WD up to 3 mm (p < 0.001). TFL required the laser fibre to be moved faster (5-12 mm/s) for optimal ablation, compared to 1-3 mm/s for the Ho:YAG lasers. TFL was unable to demonstrate ablation with unsoaked BegoStone. At any given power, similar ablation rates were achievable with all three lasers under optimised conditions. Novel pulse-modulation modes demonstrated higher ablation rates than the reference Ho:YAG laser's pulse-modulation at a range of powers and WDs. Ablation rate of Ho:YAG lasers decreased linearly with WD whereas the ablation rate of TFL decreased rapidly beyond 2 mm WD. TFL was more affected by scan speed and pre-soaking of stone than Ho:YAG lasers. Ho:YAG lasers may be more practical in clinical settings because they are less dependent on ablation technique., (© 2023. The Author(s).)

Objectives: To determine if management of ureteric stones in the UK changed during the coronavirus disease 2019 (COVID-19) pandemic and whether this affected patient outcomes., Patients and Methods: We conducted a multicentre retrospective study of adults with computed tomography-confirmed ureteric stone disease at 39 UK hospitals during a pre-pandemic period (23/3/2019-22/6/2019) and a period during the pandemic (the 3-month period after the first severe acute respiratory syndrome coronavirus-2 case at individual sites). The primary outcome was success of primary treatment modality, defined as no further treatment required for the index ureteric stone. Our study protocol was published prior to data collection., Results: A total of 3735 patients were included (pre-pandemic 1956 patients; pandemic 1779 patients). Stone size was similar between groups (P > 0.05). During the pandemic, patients had lower hospital admission rates (pre-pandemic 54.0% vs pandemic 46.5%, P < 0.001), shorter mean length of stay (4.1 vs 3.3 days, P = 0.02), and higher rates of use of medical expulsive therapy (17.4% vs 25.4%, P < 0.001). In patients who received interventional management (pre-pandemic 787 vs pandemic 685), rates of extracorporeal shockwave lithotripsy (22.7% vs 34.1%, P < 0.001) and nephrostomy were higher (7.1% vs 10.5%, P = 0.03); and rates of ureteroscopy (57.2% vs 47.5%, P < 0.001), stent insertion (68.4% vs 54.6%, P < 0.001), and general anaesthetic (92.2% vs 76.2%, P < 0.001) were lower. There was no difference in success of primary treatment modality between patient cohorts (pre-pandemic 73.8% vs pandemic 76.1%, P = 0.11), nor when patients were stratified by treatment modality or stone size. Rates of operative complications, 30-day mortality, and re-admission and renal function at 6 months did not differ between the data collection periods., Conclusions: During the COVID-19 pandemic, there were lower admission rates and fewer invasive procedures performed. Despite this, there were no differences in treatment success or outcomes. Our findings indicate that clinicians can safely adopt management strategies developed during the pandemic to treat more patients conservatively and in the community., (© 2022 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Objective: To present common technical and non-technical issues leading to medicolegal litigation, illustrated by a series of 54 cases, with the aim of using these examples to prevent harm to patients and to prevent surgeons from having to experience the stress of litigation., Methods: A series of 78 medicolegal litigation cases reviewed by a single expert witness over 13 years from 2008 to 2021 was analysed by two reviewers. Twenty-nine cases were identified as having a non-technical learning point and 25 were identified as having a technical learning point. These are discussed using illustrative examples and the steps that could have avoided these issues are considered., Results: All major issues and themes are illustrated with cases demonstrating the errors that lead to litigation and the often-simple steps that can be taken to avoid them. Out of 29 non-technical issues, 13 involved consent issues (45%), eight involved delays in treatment (28%) and eight involved failure to provide adequate safeguarding advice (28%). Out of 25 technical issues, 13 cases involved intra-operative problems (52%) including nine ureteric injuries, eight involved errors or omissions in the immediate preoperative period (32%) and four resulted from decisions around emergency decompression of the obstructed infected kidney. These emergency cases featured complications of amputation (two out of four) and death (one out of four). These decisions are complex and there are many subtleties to these cases, which are discussed in detail., Conclusion: We hope that this case series highlights the potentially catastrophic outcomes of even small errors of judgement, and allows careful stone surgeons to learn from the experiences of those unfortunate others without having to encounter these situations themselves., (© 2022 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Ureteroscopy with laser lithotripsy has evolved as the most commonly used technique for the treatment of kidney stones. Automated segmentation of kidney stones and the laser fiber is an essential initial step to performing any automated quantitative analysis, particularly stone-size estimation, that can be used by the surgeon to decide if the stone requires further fragmentation. However, factors such as turbid fluid inside the cavity, specularities, motion blur due to kidney movements and camera motion, bleeding, and stone debris impact the quality of vision within the kidney, leading to extended operative times. To the best of our knowledge, this is the first attempt made towards multi-class segmentation in ureteroscopy and laser lithotripsy data. We propose an end-to-end convolution neural network (CNN) based learning framework for the segmentation of stones and laser fiber. The proposed approach utilizes two sub-networks: (I) HybResUNet, a hybrid version of residual U-Net, that uses residual connections in the encoder path of the U-Net to improve semantic predictions, and (II) a DVFNet that generates deformation vector field (DVF) predictions by leveraging motion differences between the adjacent video frames which is then used to prune the prediction maps. We also present ablation studies that combine different dilated convolutions, recurrent and residual connections, atrous spatial pyramid pooling, and attention gate models. Further, we propose a compound loss function that significantly boosts the segmentation performance in our data. We have also provided an ablation study to determine the optimal data augmentation strategy for our dataset. Our qualitative and quantitative results illustrate that our proposed method outperforms state-of-the-art methods such as UNet and DeepLabv3+ showing a DSC improvement of 4.15% and 13.34%, respectively, in our in vivo test dataset. We further show that our proposed model outperforms state-of-the-art methods on an unseen out-of-sample clinical dataset with a DSC improvement of 9.61%, 11%, and 5.24% over UNet, HybResUNet, and DeepLabv3+, respectively in the case of the stone class and an improvement of 31.79%, 22.15%, and 10.42% over UNet, HybResUNet, and DeepLabv3+, respectively, in case of the laser class., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: To reassess the trends in upper urinary tract (UUT) stone disease burden and management in the UK during the last 5 years., Methods: The present paper is our third quinquennial analysis of trends in the management of renal stones in England. Data were collected using the Hospital Episode Statistics database for the years 2015-2020 inclusive. These were then analysed, summarized and presented., Results: The number of UUT stone episodes increased by 2.2% from 86 742 in 2014-2015 to 88 632 in 2019-2020 but annual prevalence remained static at 0.14%. The number of UUT stone episodes in those of working age has remained static but increased by 9% for patients aged > 60 years (from 27 329 to 29 842). The number of shockwave lithotripsy (SWL) treatments decreased by 6.8%. There was a further increase in the use of ureteroscopy (URS) between 2015 and 2020 of 18.9%. Within this subgroup, flexible URS had the most rapid increase in use, with a rise of 20.4% from 7108 to 8558 recorded cases. Over the 20-year period from 2000 to 2020 there was a remarkable 257% increase in URS cases. There was a further decline in open surgery for UUT stone disease by 40%. Stone surgery day-case numbers have increased by 14.7% (from 31 014 to 35 566), with a corresponding decline in the number of bed days of 14.3%. Emergency cases increased by 40%, while elective cases saw a slight increase of 1.9%., Conclusion: The present study shows a plateauing in the prevalence of UUT stone disease in England in the last 5 years, with a move towards day-case procedures and an increase in the proportion of emergency work. For the first time in England, URS has overtaken SWL as the most common procedure for treating UUT stone disease, which might reflect patients' or physicians' preference for a more effective definitive treatment., (© 2022 BJU International.)

Objective: To systematically review the natural history of small asymptomatic kidney and residual stones, as the incidental identification of small, asymptomatic renal calculi has risen with increasing use of high-resolution imaging., Materials and Methods: We reviewed the natural history of small asymptomatic kidney and residual stones using the Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. We searched MEDLINE, Scopus, EMBASE, EBSCO, Cochrane library and Clinicaltrials.gov using themes of 'asymptomatic', 'nephrolithiasis', 'observation', 'symptoms', 'admission', 'intervention' and similar allied terms for all English language articles from 1996 to 2020 (25 years). Inclusion criteria were studies with ≥50 patients, stones ≤10 mm, and a mean follow-up of ≥24 months. Primary outcomes were occurrence of symptoms, emergency admission, and interventions., Results: Our literature search returned 2247 results of which 10 papers were included in the final review. Risk of symptomatic episodes ranged from 0% to 59.4%. Meta-analysis did not identify any significant difference in the likelihood of developing symptoms when comparing stones <5 mm to those >5 mm, nor those <10 mm to those >10 mm. Risk of admission varied from 14% to 19% and the risk of intervention from 12% to 35%. Meta-analysis showed a significantly decreased likelihood of intervention for stones <5 vs >5 mm and <10 vs >10 mm. Studies had variable risk of bias due to heterogeneous reporting of outcome measures with significant likelihood that observed differences in results were compatible with chance alone (Symptoms: I 2 =0%, Cochran's Q = 3.09, P = 0.69; Intervention: I 2 =0%, Cochran's Q = 1.76, P = 0.88)., Conclusions: The present systematic review indicates that stone size is not a reliable predictor of symptoms; however, risk of intervention is greater for stones >5mm vs <5 mm and >10 vs <10 mm. This review will inform urologists as they discuss management strategies with patients who have asymptomatic renal stones and offer insight to committees during the development of evidence-based guidelines., (© 2021 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

The upper urinary tract (UUT) consists of kidneys and ureters, and is an integral part of the human urogenital system. Yet malfunctioning and complications of the UUT can happen at all stages of life, attributed to reasons such as congenital anomalies, urinary tract infections, urolithiasis and urothelial cancers, all of which require urological interventions and significantly compromise patients' quality of life. Therefore, many models have been developed to address the relevant scientific and clinical challenges of the UUT. Of all approaches, fluid mechanical modeling serves a pivotal role and various methods have been employed to develop physiologically meaningful models. In this article, we provide an overview on the historical evolution of fluid mechanical models of UUT that utilize theoretical, computational, and experimental approaches. Descriptions of the physiological functionality of each component are also given and the mechanical characterizations associated with the UUT are provided. As such, it is our aim to offer a brief summary of the current knowledge of the subject, and provide a comprehensive introduction for engineers, scientists, and clinicians who are interested in the field of fluid mechanical modeling of UUT. This article is categorized under: Cancer > Biomedical Engineering Infectious Diseases > Biomedical Engineering Reproductive System Diseases > Biomedical Engineering., (© 2021 The Authors. WIREs Mechanisms of Disease published by Wiley Periodicals LLC.)

Introduction: Renal stones are common, with a lifetime prevalence of 10% in adults. Global incidence is increasing due to increases in obesity and diabetes, with these patient populations being more likely to suffer renal stone disease. Flank pain from stones (renal colic) is the most common cause of emergency admission to UK urology departments. Stones most commonly develop in the lower pole of the kidney (in ~35% of cases) and here are least likely to pass without intervention. Currently there are three technologies available within the UK National Health Service to remove lower pole kidney stones: extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and flexible ureterorenoscopy (FURS) with laser lithotripsy. Current evidence indicates there is uncertainty regarding the management of lower pole stones, and each treatment has advantages and disadvantages. The aim of this trial is to determine the clinical and cost effectiveness of FURS compared with ESWL or PCNL in the treatment of lower pole kidney stones., Methods: The PUrE (PCNL, FURS and ESWL for lower pole kidney stones) trial is a multi-centre, randomised controlled trial (RCT) evaluating FURS versus ESWL or PCNL for lower pole kidney stones. Patients aged ≥16 years with a stone(s) in the lower pole of either kidney confirmed by non-contrast computed tomography of the kidney, ureter and bladder (CTKUB) and requiring treatment for a stone ≤10 mm will be randomised to receive FURS or ESWL (RCT1), and those requiring treatment for a stone >10 mm to ≤25 mm will be randomised to receive FURS or PCNL (RCT2). Participants will undergo follow-up by questionnaires every week up to 12 weeks post-intervention and at 12 months post-randomisation. The primary clinical outcome is health status measured by the area under the curve calculated from multiple measurements of the EuroQol five dimensions five-level version (EQ-5D-5L) questionnaire up to 12 weeks post-intervention. The primary economic outcome is the incremental cost per quality-adjusted life year gained at 12 months post-randomisation., Discussion: The PUrE trial aims to provide robust evidence on health status, quality of life, clinical outcomes and resource use to directly inform choice and National Health Service provision of the three treatment options., Trial Registration: ISRCTN: ISRCTN98970319. Registered on 11 November 2015.

Introduction: We assessed the clinical performance of a new digital single-use flexible ureteroscope (UscopePU3022)., Material and Methods: A prospective cohort study was carried out across 11 centers (July-Oct. 2017). The UscopePU3022 was assessed regarding ease of insertion; deflection, image quality, maneuverability and overall performance using either a visual analog* or Likert scale., Results: A total of 56 procedures were performed in 11 centers (16 surgeons) with the indication being renal stones in 83%. The median score for ease of scope insertion was 10 (3-10). Intraoperative maneuverability was rated as 'good' in 38% and 'very good' in 52%. Visual quality was rated as 'poor or bad' in 18%, 'fair' in 37% and 'good or very good' in 43%. Two scopes failed intraoperatively (4%). Preoperative and postoperative median upward and downward deflection was 270 degrees. Compared to standard flexible ureteroscopy (f-URS) maneuverability was rated as 'equivalent' in 30% and 'better' in 60%; visual quality was 'worse' in 38% and 'equivalent or better' in 62%; limb fatigue scores were 'better' in 86%; and overall performance was 'worse' in 55% and 'equivalent or better' in 45%., Conclusions: UscopeTM3022 performed well with regards to maneuverability, deflection and limb fatigue and appears to be at least non-inferior to standard f-URS with regards to these parameters. Poor image quality is a concern for UscopePU3022 with it receiving a low overall performance rating when compared to standard f-URS. Despite this it scored highly when investigators were asked if they would use it in their practice if it was cost-effective to do so.

Purpose: The objective of this study was to evaluate the prevalence of urinary metabolic abnormalities in patients with urolithiasis and their potential risk factors., Methods: A total of 905 stone patients were evaluated in a prospective trial from February 2000 to January 2012. Inclusion criteria were as follows: history and/or imaging tests confirming at least 2 separate or concurrent stone episodes; creatinine clearance ≥ 60 mL/min; and negative proteinuria and urine culture. Metabolic study consisted of two 24-h urine collections separated by a period of 3 months for dosing Ca, P, uric acid, Na, K, Mg, oxalate, and citrate. Serum levels of Ca, P, uric acid, Na, K, Cl, Mg, creatinine, and glucose were assessed. Urinary pH and urinary acidification tests were also performed., Results: A total of 735 patients were included, with a mean age of the 40 ± 1.0 year; 96.8 % of patients presented diagnosis of one or more urinary metabolic abnormalities. The most prevalent metabolic abnormalities were hypercalciuria (50.8 %), hypomagnesuria (50.1 %), hypocitraturia (35.4 %), and hyperuricosuria (30.7 %). Body weight was significantly higher in patients with hyperuricosuria (81.20 ± 15.67 kg vs. 70.17 ± 14.13 kg, respectively, p = 0.001). Urinary sodium was significantly higher in patients with hypercalciuria than without (246.97 ± 103.9 mEq/24 h vs. 200.31 ± 91.6 mEq/24 h, p = 0.001) and hyperuricosuria compared to without (283.24 ± 107.95 mEq/24 h vs. 198.57 ± 85.3 mEq/24 h, p = 0.001)., Conclusion: Urinary metabolic disturbances were diagnosed in 96.8 % of patients in the study. These results warrant metabolic study and follow-up in patients with recurrent lithiasis in order to decrease recurrence rate through specific treatments, modification in alimentary, and behavioral habits.

Purpose: The Post-Ureteroscopic Lesion Scale (PULS) offers a simple grading system for the description of ureteral lesions after ureteroscopy. In this article, we present the results of a video-based multicenter evaluation of the inter-rater reliability of clinically important PULS grades 0-3., Methods: Video sequences at the end of ureteroscopy (final passage) were recorded for 100 consecutive patients at a single institution and assessed by experienced urologists (n = 20) and senior residents (n = 17) at 19 international centers. The cohort included only patients with lesions grades 0-3 (with grades 2 and 3 subsumed as 2 + since distinction is defined by an extravasation of contrast medium in fluoroscopy). The gradings were evaluated for inter-rater reliability and in terms of simplicity, validity, comprehensibility, reproducibility, and usefulness., Results: Overall, inter-rater reliability was high (Kendall's W = 0.69, p < 0.001) and was comparable between specialists (Kendall's W = 0.69, p < 0.001) and residents (Kendall's W = 0.71, p < 0.001). The matched ratings showed grade 0 in 43.0 % of patients and grades 1 or 2 + in 44.0 and 13.0 % of patients, respectively. Results of the questionnaires indicated a high degree of acceptance, with an overall rating of 1.76 (1.64-1.93 for different items, scale 1-6)., Conclusions: Inter-rater reliability of the endoscopically assessable PULS was high among urologists with different levels of experience in different countries worldwide. The validated PULS system may be used for standardized reporting of ureteral lesions/injuries after ureteroscopy. In addition, PULS will enable more selective standardization of indications for postoperative DJ stenting based on the randomized controlled trials.

Introduction: The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers., Materials and Methods: Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment., Results: At baseline, 20 of the 26 patients (77%) had a high PSF score (> 0.5). Of the 26 patients, 17 (65%) showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42%) changed from a high risk (PSF > 0.5) to a low risk (PSF < 0.5) and 6 patients reduced their risk score but did not change risk category. Six (23%) patients remained in a high risk category (> 0.5) during both assessments., Conclusions: The PSF score reduced following medical treatment in the majority of patients in this cohort.

This report describes a case whereby a ureteric stent became knotted during removal and lodged within the upper ureter. The authors describe a novel minimally invasive technique to remove the knotted ureteric stent using the holmium laser.

The 2009 pandemic influenza A (H1N1) has been recognized to cause neurological complications including seizures and encephalopathy. We identified 18 children with 2009 H1N1 influenza and neurological complications from first and second wave activity, and compared characteristics to seasonal influenza. Seizures, encephalopathy, and status epilepticus were common presentations. Focal neurological symptoms persisted in 22% of patients at discharge. Compared to seasonal influenza, patients with pandemic 2009 influenza were more likely to have encephalopathy, focal neurological findings, aphasia, and abnormal electroencephalographic findings. In addition, we noted a trend toward heightened neurological complications following second wave influenza activity.

Some commercial batches of dichloroacetic acid (DCA) contain traces of chloral (trichloroacetaldehyde). Using such DCA to effect detritylation during solid-phase oligonucleotide synthesis results in the formation of a family of process impurities in which the atoms of chloral (Cl3CCHO) are incorporated between the 5'-oxygen and phosphorus atoms of an internucleotide linkage. The structure was elucidated by HPLC with UV and MS detection, digestion of the oligonucleotide, synthesis of model compounds, and 1H and 31P NMR spectroscopy. By understanding the chemistry behind its formation, we are now able to limit levels of this impurity in synthetic oligonucleotides by limiting chloral in DCA.

Multiple phosphorothioate oligonucleotides containing a 3'-terminal negative charge were synthesized and characterized. Influence of the added negative charge on activation of duplexes by RNase H was investigated. No additional help in recruitment of RNase H was observed.

A phosphorothioate-linked oligonucleotide bearing a 3'-terminal phosphorothioate monoester has been synthesized and characterized. This oligonucleotide has been identified as a process-related impurity formed during synthesis of ISIS 2302. Biological properties of the compound have been determined. Based on these data, it can be concluded that this species (3'-TPT) has biological properties similar to parent drug.