Oxygen extraction efficiency of the tidally-ventilated rectal gills of dragonfly nymphs.

Dragonfly nymphs breathe water using tidal ventilation, a highly unusual strategy in water-breathing animals owing to the high viscosity, density and low oxygen (O2) concentration of water. This study examines how well these insects extract O2 from the surrounding water during progressive hypoxia. Nymphs were attached to a custom-designed respiro-spirometer to simultaneously measure tidal volume, ventilation frequency and metabolic rate. Oxygen extraction efficiencies (OEE) were calculated across four partial pressure of oxygen (pO2) treatments, from normoxia to severe hypoxia. While there was no significant change in tidal volume, ventilation frequency increased significantly from 9.4 ± 1.2 breaths per minute (BPM) at 21.3 kPa to 35.6 ± 2.9 BPM at 5.3 kPa. Metabolic rate increased significantly from 1.4 ± 0.3 µl O2 min-1 at 21.3 kPa to 2.1 ± 0.4 µl O2 min-1 at 16.0 kPa, but then returned to normoxic levels as O2 levels declined further. OEE of nymphs was 40.1 ± 6.1% at 21.3 kPa, and did not change significantly during hypoxia. Comparison to literature shows that nymphs maintain their OEE during hypoxia unlike other aquatic tidal-breathers and some unidirectional breathers. This result, and numerical models simulating experimental conditions, indicate that nymphs maintain these extraction efficiencies by increasing gill conductance and/or lowering internal pO2 to maintain a sufficient diffusion gradient across their respiratory surface.

Iron-Mediated Dialkylation of Alkenylarenes with Benzyl Bromides.

We disclose a method for the dibenzylation of alkenylarenes with benzyl bromides using iron powder. This reaction generates branched alkyl scaffolds adorned with functionalized aryl rings through the formation of two new C(sp3)-C(sp3) bonds at the vicinal carbons of alkenes. This protocol tolerates electron-rich, electron-neutral, and electron-poor benzyl bromides and alkenylarenes. Mechanistic studies suggest the formation of benzylic radical intermediates as a result of single-electron transfer from the iron, which is intercepted by alkenylarenes.

Effect of Screw Length in Volar Plating for Intra-articular Distal Radius Fractures: A Biomechanical Study.

PURPOSE: The purpose of this study was to compare the effect of varying screw lengths on load to failure and retention of the dorsal ulnar corner fragment after fixation of comminuted intra-articular distal radius fractures in a cadaveric model. METHODS: Twenty-four fresh frozen cadaveric forearms were subjected to a standardized distal radius osteotomy to mimic an intra-articular fracture pattern. Dual X-ray absorptiometry scans were performed to ensure minimal variability in bone density. All fractures were fixed with a volar locking plate and distal locking screws. Three different lengths of distal locking screws were used in each group of eight specimens to simulate the clinical decision of different distal screw lengths. The screw lengths tested were bicortical, 100% of the width of the bone but unicortical, and 75% of the width of the bone and unicortical. All specimens were preconditioned with cyclic axial loading and then axially loaded using matching acrylic resin molds to clinical failure and fragment displacement as detected by a motion analysis system. Retention or loss of the dorsal ulnar corner fragment during loading was recorded as a binary variable. RESULTS: Between the three groups, there were no statistically significant differences in precycling stiffness, postcycling stiffness, load at 2 mm displacement of the dorsal ulnar corner, or force at failure. The group with 75% length screws had a significantly higher loss of reduction of the dorsal ulnar corner (86%) compared with the other groups (0%). CONCLUSIONS: Varying screw lengths did not affect the stiffness or overall loads to failure of axially loaded specimens. However, the 75% length screws did not reliably secure the dorsal ulnar corner fragments. Although this did not significantly affect the overall load to failure of the construct, displacement of this fragment may have implications for rotation of the forearm through the distal radioulnar joint. CLINICAL RELEVANCE: Surgeons should consider the utilization of full-length unicortical locking screws to ensure adequate fixation of the dorsal ulnar corner. TYPE OF STUDY/LEVEL OF EVIDENCE: Biomechanical study V.

Interception and Synthetic Application of Diradical and Diene Forms of Dual-Nature Azabicyclic o-Quinodimethanes Generated by 6π-Azaelectrocyclization.

We demonstrate that 2-alkenylarylaldimines and ketimines undergo thermal 6π-azaelectrocyclization to generate a wide range of azabicyclic o-quinodimethanes (o-QDMs). These o-QDMs exist as a hybrid of a diene and a benzylic diradical. The diradical nature was confirmed by their ability to undergo dimerization and react with H-atom donor, 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and O2. In addition, the interception of the diradicaloid o-QDMs by H-atom transfer was used to synthesize five tetrahydroisoquinoline alkaloids and related bioactive molecules. The diene form can undergo [4+2] cycloaddition reactions with different dienophiles to generate bridged azabicycles in high endo:exo selectivity. The azabicyclic o-QDMs can be generated for [4+2] cycloaddition from a wide range of electronically and sterically varied 2-alkenylarylimines, including mono, di, tri and tetrasubstituted alkenes, and imines derived from arylamine, alkylamine (1°, 2°, 3°), benzylamine, benzylsulfonamide and Boc-amine.

Does Perioperative Testosterone Predict Post-Prostatectomy Genomic Risk Score?

PURPOSE: The role of endogenous testosterone in de novo prostate cancer pathogenesis in humans remains unclear. The effect of testosterone on the tumor genome is not explored. We sought to explore the correlation between perioperative testosterone level and genomic risk score in a cohort of men who underwent radical prostatectomy. MATERIALS AND METHODS: We included patients who underwent radical prostatectomy (2013-2018) and had adverse pathological features in their final surgical specimens (positive margin, and/or pT3a or higher). The outcome of interest was the genomic risk score: low (<0.45), intermediate (0.45-0.6) and high (>0.6). The associations between serum testosterone level and 188 gene expression-based signatures were examined. Secondary outcomes of interest included biochemical recurrence and receipt of secondary treatment. RESULTS: The median genomic risk score was lower in the low testosterone group compared to the intermediate and normal testosterone groups (0.38 vs 0.52 vs 0.53, respectively; p=0.049). There was no difference in biochemical recurrence-free survival between the 3 testosterone groups (p=0.9). Patients with low testosterone levels had higher odds of receiving secondary treatment (OR: 2.27; 95% CI: 1.14-4.50; p=0.02) than those with normal levels. A total of 43 (of 188) gene expression signatures were associated with testosterone level (p <0.05). In total, 33 signatures were positively associated with serum testosterone levels, including 12 signatures involved in DNA repair pathways. CONCLUSIONS: This is the first study to assess the correlation of preoperative testosterone level on the tumor transcriptome and showed no clinical correlation between pre-defined genomic risk score groups and testosterone groups. This study adds to the notion of the limited role of endogenous testosterone on the development of de novo high-risk localized prostate cancer.

"Transcanal view" computed tomography reformat: Applications for transcanal endoscopic ear surgery.

PURPOSE: Transcanal endoscopic ear surgery (TEES) is an increasingly used surgical approach for otologic surgeries, but no en face preoperative imaging format currently exists. We aim to assess the utility of a transcanal high resolution computed tomography (HRCT) reformat suitable for TEES preoperative planning. MATERIALS AND METHODS: Preoperative HRCTs of patients with middle ear pathologies (cholesteatoma, otosclerosis, and glomus tympanicum) who underwent TEES were obtained. Axial image series were rotated and reformatted -90 or +90 degrees for left and right ear surgeries, respectively, where additional rotation along the left-right axis was performed to align the transcanal series with the plane of the external auditory canal. Quantitative measurements of middle ear structures were recorded. Consecutive transcanal reformatted sections were then reviewed to identify critical middle ear anatomy and pathology with corresponding TEES cases. RESULTS: The aforementioned methodology was used to create three transcanal view HRCTs. The mean left-right axis degree of rotation was 4.0 ± 2.2 degrees. In the cholesteatoma transcanal HRCT, areas of cholesteatoma involvement in middle ear compartments (e.g. epitympanum) and eroded ossicles were successfully identified in the corresponding case. In the otosclerosis transcanal HRCT, areas for potential otosclerotic involvement were visualized such as the round window as well as a low-hanging facial nerve. In the glomus tympanicum transcanal HRCT, the span of the glomus tympanicum was successfully visualized in addition to a high riding jugular bulb. CONCLUSION: A transcanal HRCT reformat may aid preoperative planning for middle ear pathologies. This novel reformat may help highlight patient-specific anatomy.

Development and validation of the Durham Risk Score for estimating suicide attempt risk: A prospective cohort analysis.

BACKGROUND: Worldwide, nearly 800,000 individuals die by suicide each year; however, longitudinal prediction of suicide attempts remains a major challenge within the field of psychiatry. The objective of the present research was to develop and evaluate an evidence-based suicide attempt risk checklist [i.e., the Durham Risk Score (DRS)] to aid clinicians in the identification of individuals at risk for attempting suicide in the future. METHODS AND FINDINGS: Three prospective cohort studies, including a population-based study from the United States [i.e., the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) study] as well as 2 smaller US veteran cohorts [i.e., the Assessing and Reducing Post-Deployment Violence Risk (REHAB) and the Veterans After-Discharge Longitudinal Registry (VALOR) studies], were used to develop and validate the DRS. From a total sample size of 35,654 participants, 17,630 participants were selected to develop the checklist, whereas the remaining participants (N = 18,024) were used to validate it. The main outcome measure was future suicide attempts (i.e., actual suicide attempts that occurred after the baseline assessment during the 1- to 3-year follow-up period). Measure development began with a review of the extant literature to identify potential variables that had substantial empirical support as longitudinal predictors of suicide attempts and deaths. Next, receiver operating characteristic (ROC) curve analysis was utilized to identify variables from the literature review that uniquely contributed to the longitudinal prediction of suicide attempts in the development cohorts. We observed that the DRS was a robust prospective predictor of future suicide attempts in both the combined development (area under the curve [AUC] = 0.91) and validation (AUC = 0.92) cohorts. A concentration of risk analysis found that across all 35,654 participants, 82% of prospective suicide attempts occurred among individuals in the top 15% of DRS scores, whereas 27% occurred in the top 1%. The DRS also performed well among important subgroups, including women (AUC = 0.91), men (AUC = 0.93), Black (AUC = 0.92), White (AUC = 0.93), Hispanic (AUC = 0.89), veterans (AUC = 0.91), lower-income individuals (AUC = 0.90), younger adults (AUC = 0.88), and lesbian, gay, bisexual, transgender, and queer or questioning (LGBTQ) individuals (AUC = 0.88). The primary limitation of the present study was its its reliance on secondary data analyses to develop and validate the risk score. CONCLUSIONS: In this study, we observed that the DRS was a strong predictor of future suicide attempts in both the combined development (AUC = 0.91) and validation (AUC = 0.92) cohorts. It also demonstrated good utility in many important subgroups, including women, men, Black, White, Hispanic, veterans, lower-income individuals, younger adults, and LGBTQ individuals. We further observed that 82% of prospective suicide attempts occurred among individuals in the top 15% of DRS scores, whereas 27% occurred in the top 1%. Taken together, these findings suggest that the DRS represents a significant advancement in suicide risk prediction over traditional clinical assessment approaches. While more work is needed to independently validate the DRS in prospective studies and to identify the optimal methods to assess the constructs used to calculate the score, our findings suggest that the DRS is a promising new tool that has the potential to significantly enhance clinicians' ability to identify individuals at risk for attempting suicide in the future.

Impact of the COVID-19 Pandemic on Urological Care Delivery in the United States.

PURPOSE: We examined changes in urological care delivery due to COVID-19 in the U.S. based on patient, practice, and local/regional demographic and pandemic response features. MATERIALS AND METHODS: We analyzed real-world data from the American Urological Association Quality (AQUA) Registry collected from electronic health record systems. Data represented 157 outpatient urological practices and 3,165 providers across 48 U.S. states and territories, including 3,297,721 unique patients, 12,488,831 total outpatient visits and 2,194,456 procedures. The primary outcome measure was the number of outpatient visits and procedures performed (inpatient or outpatient) per practice per week, measured from January 2019 to February 2021. RESULTS: We found large (>50%) declines in outpatient visits from March 2020 to April 2020 across patient demographic groups and states, regardless of timing of state stay-at-home orders. Nonurgent outpatient visits decreased more across various nonurgent procedures (49%-59%) than for procedures performed for potentially urgent diagnoses (38%-52%); surgical procedures for nonurgent conditions also decreased more (43%-79%) than those for potentially urgent conditions (43%-53%). African American patients had similar decreases in outpatient visits compared with Asians and Caucasians, but also slower recoveries back to baseline. Medicare-insured patients had the steepest declines (55%), while those on Medicaid and government insurance had the lowest percentage of recovery to baseline (73% and 69%, respectively). CONCLUSIONS: This study provides real-world evidence on the decline in urological care across demographic groups and practice settings, and demonstrates a differential impact on the utilization of urological health services by demographics and procedure type.

Urinary Diversion: Core Curriculum 2021.

Urinary diversion after cystectomy has been a historical standard for the treatment of numerous benign and malignant diseases of the bladder. Since the first published description in the early 1900s, improvements in surgical technique and a better understanding of the metabolic sequelae postoperatively have greatly enhanced patient outcomes. Both continent and incontinent diversions are available to patients after cystectomy. In appropriately selected patients, orthotopic neobladder reconstruction can offer preservation of body image and continence, and continent cutaneous diversions represent a reasonable alternative. Conduit diversion, which remains the most commonly performed diversion technique, is ideal for patients who would benefit from a less morbid surgical procedure that negates the need for self-catheterization. This installment of the Core Curriculum in Nephrology outlines numerous aspects of urinary diversion, in which a multidisciplinary approach to postoperative management at the intersection of nephrology and urology is required to effectively optimize patient outcomes. This article includes a discussion of the various reconstructive options after cystectomy as well as a comprehensive review of frequently encountered short-term and long-term metabolic abnormalities associated with altered electrolyte and acid-base homeostasis.

Adult Auditory Brainstem Implant Outcomes and Three-Dimensional Electrode Array Position on Computed Tomography.

OBJECTIVES: Factors contributing to auditory brainstem implant (ABI) outcomes are poorly understood. The aims of this study are to (1) characterize ABI electrode array position on postoperative imaging and (2) determine if variability in position is related to perceptual outcomes. DESIGN: Retrospective cohort study. Subjects were selected from the adult ABI recipient population at Massachusetts Eye and Ear. Postoperative three-dimensional (3D) computed tomography (CT) reconstruction of the head was used to measure ABI array position in 20 adult ABI recipients (17 with Neurofibromatosis Type 2 (NF2) and three non-NF2 recipients). Three-dimensional electrode array position was determined based on angles from the horizontal using posterior and lateral views and on distances between the proximal array tip superiorly from the basion (D1), laterally (D2P) and posteriorly (D2L) from the midline. Array position was correlated with perceptual data (in 15 of the 20 recipients who used their ABI). Perceptual data included the number of electrodes that provided auditory sensation, location and type of side effects, level of speech perception (from no sound to open-set word recognition of monosyllables) and the amount of charge required for auditory perception. RESULTS: Although the 3D orientation of the ABI array exhibited a variety of angles, all arrays were posteriorly tilted from the lateral view and most were medially tilted from the posterior view. ABI position relative to the basion from posterior showed mean distances of 1.71 ± 0.42 and 1.1 ± 0.29 cm for D1 and D2, respectively, and a mean D2 of 1.30 ± 0.45 cm from the lateral view. A strong linear negative correlation was found between the number of active electrodes and the distance of the proximal array tip laterally from the basion (D2P; rs = -0.73, p = 0.006) when measured in the posterior view. Although side effects were experienced in all recipients and varied in type and location across the array, electrodes in the middle part of the array tended to elicit auditory sensations while the proximal and distal tips of the array tended to elicit nonauditory side effects. Arrays with and without low charge thresholds appeared to generally overlap in position. However, the two recipients with the best (open-set) speech perception had low charge thresholds and had arrays that were tilted superiorly in the posterior view. CONCLUSION: ABI recipients with better speech perception appear to share a profile of arrays that are tilted superiorly as compared to recipients with lower speech perception levels. These ABI recipients have a high number of active electrodes (10 or more) and require less electrical charge on individual electrodes to achieve optimal stimulation.

The Use of a Brief Family Intervention to Reduce Dropout Among Veterans in Individual Trauma-Focused Treatment: A Randomized Controlled Trial.

Dropout from trauma-focused treatment for posttraumatic stress disorder (PTSD) represents a daunting challenge for the field, particularly among military and veteran samples. Family involvement may help to increase the effectiveness of PTSD treatment while also improving retention. We tested a two-session brief family intervention (BFI) protocol delivered as an adjunct to individual trauma-focused treatment among a sample of 20 veteran-family member dyads (N = 40). Willingness to participate in the family-inclusive protocol was high, with over 85% of veterans and family members who were screened agreeing to take part. All enrolled veterans were beginning a course of either cognitive processing therapy (CPT) or prolonged exposure (PE), delivered in outpatient Veterans Affairs clinics. Family members were randomized to either receive or not receive the BFI from study clinicians. In the BFI condition, 20.0% of veterans dropped out of CPT/PE before the 16-week study end; the remainder were either still attending on-protocol sessions or had completed the full protocol. In the control condition, 40.0% of veterans dropped out of CPT/PE before the end of the study. Observed significant, large-magnitude decreases in PTSD symptoms over time did not differ by condition, ESsg range = -1.12 to -2.04. Accommodation did not significantly decrease over time in either condition, ESsg range = 0.18 to -0.98. The BFI represents a promising option for veterans, family members, and clinicians who are seeking a brief, feasible, narrowly focused method for incorporating families into veterans' individual trauma-focused therapy and potentially reducing the rate of dropout.

A Comparison of Dimensional and Categorical Approaches to Characterizing the Association Between Posttraumatic Stress Disorder and Future Suicide Attempts.

The present study compared the utility of categorical (i.e., diagnostic status) and dimensional (i.e., symptom severity) approaches to measuring posttraumatic stress disorder (PTSD) in predicting future suicide attempts among participants in a nationwide, longitudinal study of U.S. military veterans who were deployed in support of operations in Iraq or Afghanistan after the September 11, 2001, terrorist attacks (9/11) and were enrolled in Veterans Health Administration services (N = 1,649). Following an initial assessment of PTSD symptoms, we assessed for suicide attempts at two subsequent time points (M = 28.74 months, SD = 8.72 and M = 55.11 months, SD = 6.89 following the initial assessment). Between the initial and final assessments, 125 participants (7.58%) made at least one suicide attempt. All categorical and dimensional indicators of PTSD predicted suicide attempts at both time points except the categorical indicator for reexperiencing symptoms. Categorical indicators predicting suicide attempts demonstrated excellent sensitivity but poor specificity and overall accuracy. The point along the continuum at which PTSD symptom severity was most accurate regarding the prediction of future suicide attempts was well above the threshold previously established as indicating a probable diagnosis. Although this score was less sensitive than diagnostic indicators, it demonstrated greater specificity and overall accuracy in predicting future suicide attempts. The present results indicate that veterans whose PTSD symptoms satisfy the diagnostic criteria have a higher risk of future suicide attempts, but this risk appears to be even higher for veterans with symptom levels above the diagnostic threshold.

Urologic emergencies before and after COVID-19: a retrospective chart review.

INTRODUCTION During the coronavirus disease 2019 (COVID-19) pandemic, decreased presentations for various emergent conditions have been observed. Our objective was to compare the volume of patients with urologic emergencies presenting to emergency departments (EDs) within a single health system before and after the onset of the COVID-19 pandemic. MATERIALS AND METHODS: A retrospective chart review was performed for 3 EDs within a single health system in the United States to identify all ED consults to urology from January 1, 2019 to May 31, 2020. For emergent consults, covariates were extracted, including demographic information, insurance status, Charlson Comorbidity Index (CCI) score, travel distance from home to the ED, and whether the patient had seen a provider in the hospital system before. Data were compared between COVID-19 months (March-May 2020) and corresponding months in 2019. RESULTS: The study period encompassed 1,179 consults and 373 urologic emergencies. We observed not only a 22% decrease in urologic presentations to the ED compared to corresponding months in 2019, but also a 54% decrease in the proportion of urologic presentations that were truly emergent. For patients with emergent diagnoses, April 2020 saw an increase in Medicare/Medicaid coverage and a decrease in private insurance, May 2020 saw a decreased travel distance from home to the ED, and March and May 2020 saw an increase in patients who had previously seen a health system provider outside of the ED. No changes were seen in demographic characteristics or CCI. CONCLUSIONS: During the early COVID-19 pandemic, urologic emergencies within a single health system decreased by 54% compared to the corresponding months pre-pandemic. Those who do present for care may be influenced by both locality and provider familiarity.

How insects transition from water to air: Respiratory insights from dragonflies.

The transition of animal life from water onto land is associated with well-documented changes in respiratory physiology and blood chemistry, including a dramatic increase in blood pCO2 and bicarbonate, and changes in ventilatory control. However, these changes have primarily been documented among ancestrally aquatic animal lineages that have evolved to breathe air. In contrast, the physiological consequences of air-breathing animals secondarily adopting aquatic gas exchange are not well explored. Insects are arguably the most successful air-breathing animals, but they have also re-evolved the ability to breathe water multiple times. The juvenile life stages of many insect lineages possess tracheal gills for aquatic gas exchange, but all shift back to breathing air in their adult form. This makes these amphibiotic insects an instructive contrast to most other animal groups, being not only an ancestrally air-breathing group of animals that have re-adapted to life in water, but also a group that undergoes an ontogenetic shift from water back to air across their life cycle. This graphical review summarizes the current knowledge on how blood acid-base balance and ventilatory control change in the dragonfly during its water-to-air transition, and highlights some of the remaining gaps to be filled.

The displacement technique: a simple method for clearing maxillary sinus stubborn mucus.

BACKGROUND: Clearing thick secretions from the hidden crevices of the maxillary sinus can be challenging and can increase operative time during endoscopic sinus surgery. METHODS: We demonstrate the Displacement Technique as a user-friendly technique to address thick secretions within the maxillary sinus barring no orbital floor dehiscence. First, a wide maxillary antrostomy is performed. Then, a surgical pledget is placed in the maxillary sinus to displace the inspissated content into the nasal cavity using a curved suction. This process is repeated as necessary. CONCLUSION: The displacement technique is a simple and inexpensive method for addressing stubborn secretions.

Associations between Hospital Volume and Outcomes of Robot-Assisted Radical Prostatectomy.

PURPOSE: Robot-assisted radical prostatectomy has become the predominant surgical modality to manage localized prostate cancer in the U.S. However, there are few studies focusing on the associations between hospital volume and outcomes of robot-assisted radical prostatectomy. MATERIALS AND METHODS: We identified robot-assisted radical prostatectomies for clinically localized (cT1-2N0M0) prostate cancer diagnosed between 2010 and 2014 in the National Cancer Database. We categorized annual average hospital robot-assisted radical prostatectomy volume into very low, low, medium, high and very high by most closely sorting the final included patients into 5 equal-sized groups (quintiles). Outcomes included 30-day mortality, 90-day mortality, conversion (to open), prolonged length of stay (more than 2 days), 30-day (unplanned) readmission, positive surgical margin and lymph node dissection rates. RESULTS: A total of 114,957 patients were included in the study, and hospital volume was categorized into very low (3 to 45 cases per year), low (46 to 72), medium (73 to 113), high (114 to 218) and very high (219 or more). Overall 30-day mortality (0.12%), 90-day mortality (0.16%) and conversion rates (0.65%) were low. Multivariable logistic regressions showed that compared with the very low volume group, higher hospital volume was associated with lower odds of conversion to open surgery (OR 0.23, p <0.001 for very high), prolonged length of stay (OR 0.25, p <0.001 for very high), 30-day readmission (OR 0.53, p <0.001 for very high) and positive surgical margins (OR 0.61, p <0.001 for very high). Higher hospital volume was also associated with higher odds of lymph node dissection in the intermediate/high risk cohort (OR 3.23, p <0.001 for very high). CONCLUSIONS: Patients undergoing robot-assisted radical prostatectomy at higher volume hospitals are likely to have improved perioperative and superior oncologic outcomes compared to lower volume hospitals.

Prolonged Length of Stay After Robotic Prostatectomy: Causes and Risk Factors.

BACKGROUND: Robot-assisted radical prostatectomy (RARP) can generally be performed with 1-2 nights of postoperative monitoring before discharge from the hospital. Little is known about what causes individual patients to remain in hospital beyond the second postoperative day. METHODS: Data for RARPs performed between 2013 and 2015 were extracted from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. The fraction of cases with prolonged length of stay (PLOS) that can be reasonably attributed to complications was examined. Logistic regression was performed to identify risk factors for PLOS in the overall population and separately in the population of patients with PLOS without any perioperative complications. RESULTS: Of 11,440 patients, 10,342 (90.4%) were discharged on postoperative days 0-2; 80.6% (887/1101) of patients with PLOS did not experience any perioperative complications. The most common complication was bleeding requiring transfusion, but this was present in only 5.6% (62/1101) of patients with PLOS. Logistic regression identified predictors of PLOS as age, race, wound class, American Society of Anesthesiologists class, smoking, diabetes, dyspnea, dependent functional health status, congestive heart failure, operative time, and pelvic lymph node dissection. Results of this regression were insensitive to the exclusion of patients who experienced no perioperative complications. CONCLUSIONS: This study utilizes logistic regression on NSQIP data to identify risk factors for PLOS after RARP and, in particular, to evaluate the role of postoperative complications in PLOS. The analysis shows that postoperative complications account for a small minority of cases of PLOS after RARP.

Synthesis and Characterization of Cyanobutadiene Isomers-Molecules of Astrochemical Significance.

Four cyanobutadiene isomers of considerable interest to the organic chemistry, molecular spectroscopy, and astrochemistry communities were synthesized in good yields and isolated as pure compounds: (E)-1-cyano-1,3-butadiene (E-1), (Z)-1-cyano-1,3-butadiene (Z-1), 4-cyano-1,2-butadiene (2), and 2-cyano-1,3-butadiene (3). A diastereoselective synthesis was developed to generate (E)-1-cyano-1,3-butadiene (1) (10:1 E/Z) via tandem SN2 and E2' reactions. The potential energy surfaces of the E2' reactions leading to (E)- and (Z)-1-cyano-1,3-butadiene (1) were analyzed by density functional theory calculations, and the observed diastereoselectivity was rationalized in the context of the Curtin-Hammett principle. The preparation of pure samples of these reactive compounds enables measurement of their laboratory rotational spectra, which are the critical data needed to search for these species in space by radioastronomy.

Superior Canal Dehiscence Similarly Affects Cochlear Pressures in Temporal Bones and Audiograms in Patients.

OBJECTIVES: The diagnosis of superior canal dehiscence (SCD) is challenging and audiograms play an important role in raising clinical suspicion of SCD. The typical audiometric finding in SCD is the combination of increased air conduction (AC) thresholds and decreased bone conduction thresholds at low frequencies. However, this pattern is not always apparent in audiograms of patients with SCD, and some have hearing thresholds that are within the normal reference range despite subjective reports of hearing impairment. In this study, we used a human temporal bone model to measure the differential pressure across the cochlear partition (PDiff) before and after introduction of an SCD. PDiff estimates the cochlear input drive and provides a mechanical audiogram of the temporal bone. We measured PDiff across a wider frequency range than in previous studies and investigated whether the changes in PDiff in the temporal bone model and changes of audiometric thresholds in patients with SCD were similar, as both are thought to reflect the same physical phenomenon. DESIGN: We measured PDiff across the cochlear partition in fresh human cadaveric temporal bones before and after creating an SCD. Measurements were made for a wide frequency range (20 Hz to 10 kHz), which extends down to lower frequencies than in previous studies and audiograms. PDiff = PSV- PST is calculated from pressures measured simultaneously at the base of the cochlea in scala vestibuli (PSV) and scala tympani (PST) during sound stimulation. The change in PDiff after an SCD is created quantifies the effect of SCD on hearing. We further included an important experimental control-by patching the SCD, to confirm that PDiff was reversed back to the initial state. To provide a comparison of temporal bone data to clinical data, we analyzed AC audiograms (250 Hz to 8kHz) of patients with symptomatic unilateral SCD (radiographically confirmed). To achieve this, we used the unaffected ear to estimate the baseline hearing function for each patient, and determined the influence of SCD by referencing AC hearing thresholds of the SCD-affected ear with the unaffected contralateral ear. RESULTS: PDiff measured in temporal bones (n = 6) and AC thresholds in patients (n = 53) exhibited a similar pattern of SCD-related change. With decreasing frequency, SCD caused a progressive decrease in PDiff at low frequencies for all temporal bones and a progressive increase in AC thresholds at low frequencies. SCD decreases the cochlear input drive by approximately 6 dB per octave at frequencies below ~1 kHz for both PDiff and AC thresholds. Individual data varied in frequency and magnitude of this SCD effect, where some temporal-bone ears had noticeable effects only below 250 Hz. CONCLUSIONS: We found that with decrease in frequency the progressive decrease in low-frequency PDiff in our temporal bone experiments mirrors the progressive elevation in AC hearing thresholds observed in patients. This hypothesis remains to be tested in the clinical setting, but our findings suggest that that measuring AC thresholds at frequencies below 250 Hz would detect a larger change, thus improving audiograms as a diagnostic tool for SCD.

Reducing Opioid Use After Endourologic Procedures.

PURPOSE OF REVIEW: Surgeons have played a significant role in the current opioid epidemic through overprescribing practices in the postoperative setting. However, contemporary efforts have helped to decrease opioid excess, particularly in the field of urology. Minimally invasive surgery offers a unique avenue to address overuse of narcotics in the postoperative period given its emphasis on enhanced recovery. RECENT FINDINGS: Historically, the majority of the literature characterizing postoperative opioid use and its reduction has focused on non-urological surgery. However, recent studies have shown that patients undergoing urologic procedures are prescribed opioids in a similar manner as patients in other surgical specialties. Reduction strategies have been implemented through the use of regional anesthesia, enhanced recovery after surgery pathways, and the development of procedure-specific opioid prescription recommendations. Patients undergoing urologic surgery experience the same risk of opioid misuse and abuse as patients undergoing other types of surgery. However, the wide use of minimally invasive urological surgeries including robotic surgery offers a unique opportunity to reduce postoperative opioid use through multimodal and interdisciplinary protocols and standardizing guidelines.