Experience using multielectrode cardiac catheters for detection of electrophysiologic activity of the human urinary bladder.

AIM: To determine the feasibility of commercially available multielectrode cardiac electrophysiology catheters to detect electrical activity in the human bladder. METHODS: Ten subjects requiring cystoscopy for the evaluation of lower urinary tract pathology were eligible for participation in our study. After routine rigid cystoscopy with a 70° cystoscope, various multielectrode cardiac electrophysiology catheters were introduced into the bladder. One of three catheters with different electrode configurations was used per subject. Electroanatomical images of the bladder were created and spontaneous electrical activity was recorded. Subjective response to electrical stimuli delivered across the electrodes (20 mA at 5 ms pulse width, rate 100 ms) was also recorded. The responses were qualitatively compared with that from a prior study. RESULTS: Electrical activity recorded at the dome of the bladder was less than 0.5 mV and low frequency. Myopotentials resembling smooth muscle were detected at electrodes near or within the trigone. A sensory response was reported with the use of pacing stimuli, with the sensation in the trigone being reported more often than the dome of the bladder. Stimulation in the trigone triggered sensory urgency and voiding in a patient with a history of overactive bladder. CONCLUSIONS: The use of multielectrode catheters to measure human bladder electrophysiologic activity is feasible. Issues with noise reduction still exist, though to a lesser extent with the multielectrode basket design than simple quadripolar one. Sensory responses to pacing stimuli may be useful for diagnostic and therapeutic purposes in the future.

Transdermal light neuromodulation: Optogenetics in the murine urinary tract.

BACKGROUND: Optogenetics is a biologic technique that uses light to control living neurons, which have been genetically modified to express light-sensitive ion-channels. OBJECTIVES: Using an adenovirus to modify the sciatic nerves of mice, we aim to demonstrate peripheral neuromodulation of bladder pain using transdermal light. STUDY DESIGN: This pilot study is divided into: A) Confirmation and Application and B) Behavioral Step. A) Six mice were injected with AAV6-hSyn-ChR2(H134R)-eYFP virus into their sciatic nerves. This encoded an excitatory opsin, enabling light-inducible stimulation. At 4-6 weeks after injection, we induced foot pain responses with an activating blue 475 nm wavelength of light. B) Two optogenetically primed mice and two control mice underwent anesthesia and capsaicin was instilled into their bladders via catheter. The catheters were removed and the mice awoke in a chamber that exposed them to either blue 475 nm light or no light. Groin licking was scored in a binary fashion by two blinded observers. RESULTS: A) All six mice exhibited pain response to 475 nm blue light either by licking of foot or avoidance of light. B) The optogenetically primed mice had a 48% reduction in bladder pain behavior when exposed to blue 475 nm light whereas the control mice had a 18% reduction. CONCLUSION: To our knowledge this is the first demonstration of the application of optogenetics to modulate sensation in the lower urinary tract. It suggests that the process of priming peripheral nerves for optogenetic modulation is possible and can be used to study bladder pain response in mice.

A pilot study of cardiac electrophysiology catheters to map and pace bladder electrical activity.

AIMS: This is a pilot study to evaluate the feasibility of using diagnostic cardiac electrophysiology catheters for recording intrinsic urinary bladder electrical activity and for electrical pacing capture of bladder tissue. METHODS: During cystoscopy, a curved quadripolar catheter was introduced and contact was made with the right and left halves of the dome and trigone in adult female patients undergoing cystoscopy. Electrical activity was recorded, using a commercially available cardiac electrophysiologic recording system, before and during pacing at 0.5-3.0 Hz. RESULTS: Apparent spontaneous electrical depolarizations were detected in both the trigone and the dome. The amplitude of these depolarizations was in the microVolt range. During pacing, local electrical capture was noted in the trigone, but not in the dome. CONCLUSIONS: Spontaneous low-amplitude electrical activity was detected in the bladder through the use of commercially available cardiac electrophysiology equipment. While these low-level signals could represent noise, the voltage, and morphology resemble detrusor muscle action potentials previously seen in animal studies. Pacing induced local electrical capture in the trigone but not the dome.

Uterine bioimpedance combined with artificial intelligence as a means of cancer detection.

This study hypothesised that benign and tumour-bearing uterine tissue could be differentiated by their unique electrical bioimpedance patterns, with the aid of artificial intelligence. Twenty whole, ex-vivo uterine specimens were obtained at the time of hysterectomy. A total of 11 benign and 9 malignant specimens were studied. A uterine bioimpedance probe was designed to measure the tissue between the endometrial and serosal layers of the uterus. The impedance data was then analysed with multiple instance learning and principal component analysis, forms of artificial intelligence. Final pathology results for the specimens included uterine sarcoma, adenocarcinoma, carcinosarcoma, and high-grade serous carcinoma. The analysis correctly identified 78% (7/9) of the malignant specimens and 82% (9/11) of the benign specimens. The overall accuracy of our analysis was 80%. Our results demonstrate distinction between electrical impedance properties of malignant and benign uterine specimens. Bioimpedance and artificial intelligence may have potential implications in risk assessment of patients and may subsequently guide surgical decision-making regarding route of organ removal.

Production and analysis of a mammalian septin hetero-octamer complex.

The septins are filament-forming proteins found in diverse eukaryotes from fungi to vertebrates, with roles in cytokinesis, shaping of membranes and modifying cytoskeletal organization. These GTPases assemble into rod-shaped soluble hetero-hexamers and hetero-octamers in mammals, which polymerize into filaments and higher order structures. While the cell biology and pathobiology of septins are advancing rapidly, mechanistic study of the mammalian septins is limited by a lack of recombinant hetero-octamer materials. We describe here the production and characterization of a recombinant mammalian septin hetero-octamer of defined stoichiometry, the SEPT2/SEPT6/SEPT7/SEPT3 complex. Using a fluorescent protein fusion to the complex, we observed filaments assembled from this complex. In addition, we used this novel tool to resolve recent questions regarding the organization of the soluble septin complex. Biochemical characterization of a SEPT3 truncation that disrupts SEPT3-SEPT3 interactions is consistent with SEPT3 occupying a central position in the complex while the SEPT2 subunits are at the ends of the rod-shaped octameric complexes. Consistent with SEPT2 being on the complex ends, we find that our purified SEPT2/SEPT6/SEPT7/SEPT3 hetero-octamer copolymerizes into mixed filaments with separately purified SEPT2/SEPT6/SEPT7 hetero-hexamer. We expect this new recombinant production approach to lay essential groundwork for future studies into mammalian septin mechanism and function.

In Search of Mobile Applications for Urogynecology Providers.

INTRODUCTION: Thousands of medical applications (apps) are available for mobile devices. Finding accurate, health care provider-centered apps may be time consuming and frustrating for urogynecologists. The objective of this study was to identify and evaluate urogynecology (urogyn) apps using a modified APPLICATIONS scoring system. MATERIALS AND METHODS: Urogyn apps were identified from the Apple iTunes and Google Play Stores using the following 10 MeSH terms: urogynecology, incontinence, prolapse, urinary tract infection, pelvic surgery, fecal incontinence, defecation disorder, voiding disorder, urethral diverticulum, and fistula. Patient-centered and inaccurate apps were excluded. The remaining apps were evaluated with a modified APPLICATIONS scoring system, which included both objective and subjective criteria to determine each app's ability to aid in clinical decision making and to provide informational data. Objective rating components were price, paid subscription, literature referenced, in-app purchases, Internet connectivity, advertisements, text search field, interplatform compatibility and incorporated images, figures, videos, and special features. Subjective rating components were ease of navigation and presentation. RESULTS: Our search yielded 133 and 235 apps in the Apple iTunes and Google Play Stores, respectively. Only 8 apps (4 of which were in both stores) were determined to be accurate and useful; these were evaluated using the modified APPLICATIONS scoring system. The top-rated app was Practical Urology. CONCLUSION: Few accurate clinical decision-making and informational apps exist for urogynecologists. Apps varied by comprehensiveness and quality. This study highlights the importance of systematically reviewing and rating medical apps. It also emphasizes the need for developing accurate apps for urogynecologists that improve health care provider performance and patient outcomes.

Delayed Presentation of Cecal Perforation With Tension-Free Vaginal Tape.

BACKGROUND: Tension-free vaginal tape (TVT) is a popular operative treatment for stress urinary incontinence (SUI). It has a low risk of adverse events, and injuries, particularly to the bowel, are rare. Case reports that have previously discussed these injuries and subsequent removal of TVT have not provided additional insight into management of SUI after these injuries occur. CASE: A postmenopausal woman with persistent SUI presented more than 1 year after TVT placement with bowel perforation incidentally discovered on routine screening colonoscopy. She underwent removal of the TVT and subsequent placement of a fascial sling with postoperative resolution of SUI. CONCLUSION: This case provides additional evidence for bowel injury as a postoperative TVT complication and describes an approach to complicated TVT and persistent SUI.

In vitro analysis of a nanocrystalline silver-coated surgical mesh.

BACKGROUND AND PURPOSE: One million nosocomial infections occur each year in patients with prosthetic devices. We analyzed a polypropylene mesh coated with nanocrystalline silver particles (NCSP) as a means of preventing such infections. METHODS: Nanocrystalline silver was applied to polypropylene mesh using physical vapor deposition in three doses: low (0.31 mg/cm(2)), medium (0.64 mg/cm(2)), and high (1.13 mg/cm(2)). The zone of inhibition (ZOI) test was conducted by incubating either uncoated polypropylene mesh (UM) or silver-coated mesh (CM) with and without various amounts of bovine serum albumin (BSA) and then on agar plates with Staphylococcus aureus and calculating the ZOI. The bactericidal effects of the NCSP-coated meshes were assessed by incubating either UM or CM in medium with S. aureus and performing serial dilutions at 4 and 8 h. Scanning electron microscopy (SEM) was used to examine the surface of UM and CM with and without bacterial incubation. RESULTS: There was an increasing ZOI for low-, medium-, and high-dose CM and no ZOI for UM (p < 0.001 for all CM compared with UM). Incubating the mesh with various amounts of BSA produced persistent ZOIs with the medium- and high-dose CM; however, the low-dose CM became attenuated by such treatment, with no ZOI being seen with meshes incubated in 10% BSA. All concentrations of CM were bactericidal, as no bacteria grew at 8 h of incubation. The SEM images showed clusters of S. aureus on the surface of UM and no clusters on CM. CONCLUSIONS: The CM demonstrated significant bactericidal activity compared with UM. Nanocrystalline silver particles may decrease the incidence of postoperative prosthetic mesh infections and be useful as a coating for other prosthetic materials.