Early Post-Operative Events after Urethroplasty in Obese Patients: A Multi-Institutional Retrospective Series.

OBJECTIVE: To compare early urethroplasty outcomes in non-obese, obese and morbidly obese patients undergoing urethroplasty for urethral stricture disease. The impact of obesity on outcomes is poorly understood but will be increasingly important as obesity continues to rise. METHODS: Patients underwent urethroplasty at one of five institutions between January 2016 and December 2020. Obese (BMI 30-39.9, n=72) and morbidly obese (BMI > 40, n=49) patients were compared to normal weight (BMI <25, n = 29) and overweight (BMI 25-29.9, n=51) patients. Demographics, comorbidities, and stricture characteristics were collected. Outcomes including complications, recurrence, and secondary interventions were compared using univariate and multivariate analysis. RESULTS: 201 patients (Mean BMI 34.1, Range 18.4-65.2) with mean age 52.2 years (SD=17.2) were analyzed. Median follow-up time was 3.71 months. Obese patients were younger (p=0.008), had more anterior (p<0.001), iatrogenic and LS-associated strictures (p=0.036). 60-day complication rate was 26.3% with no differences between cohorts (p= 0.788). 9.5% of patients had extravasation at catheter removal, 18.9% reported stricture recurrence, and 7.4% required additional interventions. Obese patients had greater estimated blood loss (p=0.001) and length of stay (p=0.001). On multivariate analysis, smoking associated with contrast leak (OR 7.176, 95% CI 1.13-45.5) but not recurrence or need for intervention (p=0.155, 0.927). CONCLUSIONS: Obese patients in our cohort had more anterior, iatrogenic, and LS-related strictures. However, obesity is not associated with complications, contrast leak, secondary interventions, or recurrence. Obese had higher blood loss and length of stay. Urethroplasty is safe and effective in obese patients.

Insulin receptor signaling engages bladder urothelial defenses that limit urinary tract infection.

Urinary tract infections (UTIs) commonly afflict people with diabetes. To better understand the mechanisms that predispose diabetics to UTIs, we employ diabetic mouse models and altered insulin signaling to show that insulin receptor (IR) shapes UTI defenses. Our findings are validated in human biosamples. We report that diabetic mice have suppressed IR expression and are more susceptible to UTIs caused by uropathogenic Escherichia coli (UPEC). Systemic IR inhibition increases UPEC susceptibility, while IR activation reduces UTIs. Localized IR deletion in bladder urothelium promotes UTI by increasing barrier permeability and suppressing antimicrobial peptides. Mechanistically, IR deletion reduces nuclear factor κB (NF-κB)-dependent programming that co-regulates urothelial tight junction integrity and antimicrobial peptides. Exfoliated urothelial cells or urine samples from diabetic youths show suppressed expression of IR, barrier genes, and antimicrobial peptides. These observations demonstrate that urothelial insulin signaling has a role in UTI prevention and link IR to urothelial barrier maintenance and antimicrobial peptide expression.

A career exploration didactic and simulation-based session increases student knowledge in and exposure to urology.

INTRODUCTION: Though urology attracts well-qualified applicants, students are not typically provided exposure to this smaller specialty until later in their medical education. While simulation-based training continues to supplement medical education, there is a lack of programming to teach specialty-specific procedural skills to medical students and those outside the specialty. We report a half-day simulation and didactic-based approach to increase exposure to urology to interested second-year medical students. METHODS: A half-day didactic- and simulation-based session was offered to second-year medical students (N=57). After a didactic-based overview of the specialty performed by urology providers and a surgical educator, the students participated in small-group simulations, including hands-on simulations. The students completed a post-curriculum survey measuring knowledge gains and soliciting feedback on the session. RESULTS: Students were 57.1% Caucasian, 66.7% female, with a mean age of 24.2 years; 80% stated they were potentially interested in pursuing a surgical specialty such as urology prior to the start of the session. Students reported pre- to post-curriculum gains in knowledge (mean=37%) about a career in urology and basic urologic procedures (p<0.001). Participants were also likely to recommend the curriculum to their peers (p<0.001). CONCLUSIONS: Given that exposure to urology in medical school is usually limited and offered later in training, a half-day didactic- and simulation-based experience for second-year students provides an early introduction and experience within the specialty and its common bedside procedures.

Development and Application of a Novel and Efficient Skills Assessment Tool: A Pilot Initiative to Measure Vasectomy Competency on a Smartphone.

OBJECTIVE: To develop and evaluate a mobile phone-based skills assessment tool that measures procedural competency of urology residents learning to perform a common, non-robotic urology procedure as a means of tracking current skillset and improvement over time. METHODS: The assessment tool was a Qualtrics survey accessed via a smartphone link that breaks down a vasectomy into 6 critical steps. Level of competency was measured on a scale of '1-novice' to '5-expert.' Nine residents from Post graduate year (PGY)-1 to PGY-5 were evaluated by one instructor after completing a vasectomy (86 single-side cases recorded over a 6-month period). We compared individual trainees to each other, analyzed performance (improvement) over time, and evaluated competency against cohort and program averages. RESULTS: As an example, a single resident ('Resident 2,' N = 11 cases) was compared to cohort (PGY, M = 7.5/resident) and program (all residents, M = 7.4/resident). Results indicate similar skillfulness across Step 1 (puncturing and isolation of vas and hand positioning; P > 0.1), but marginally lower competency on Step 2 (opening of vasal sheath to expose/isolate vas; vs. cohort: P = 0.076, vs. residents: P = 0.082). Significantly lower competency on Steps 3-6 (all P < 0.04) suggests targeted teaching could improve cautery technique, fascial interposition, hemostasis, and positioning of stumps. CONCLUSION: Our mobile-based skills assessment is a low cost, novel, and efficient assessment that would support current Accreditation Council for Graduate Medical Education (ACGME) goals to increase competency-based residency training. This tool is easily created and accessed, provides real-time feedback to learners, and can be used for individual and group assessment at a single timepoint or longitudinally.

Improving Access and Quality of Care for Kidney Stone Patients in an Underserved Community.

There is a call to improve Medicaid patient access to health care, enhance quality and outcomes of care, and reduce overall financial burden. We sought to build a comprehensive kidney stone program to help patients navigate through the acute and preventive aspects of stone disease by increasing multidisciplinary referrals and compliance with recommendations and decreasing no-show rates at first follow-up and repeat stone encounters after initial evaluation. A collaborative multidisciplinary program was established at our single institution consisting of urology, nephrology, and dietary specialists to be piloted over a 3-year period. Medicaid-designated patients were evaluated during new patient encounters by urology specialists and then followed for outpatient follow-up, including specialty referrals to nephrology specialists and dietitians, for targeted preventive measures. Subjective compliance reports by patients following interventions and no-show rates at subsequent follow-ups were documented. We also followed patients 6 months beyond the initial encounter to assess repeat Emergency Department (ED) visits for acute stone episodes. One hundred eighty-three Medicaid-designated stone patients were evaluated from 2018 to 2021. Sixty-eight percent of patients identified as White, 18% identified as Black/African American, and 14% identified as "Other." Patients underwent specialty referrals to nephrology or a dietician in 47% and 42% of cases, respectively. Since the program's implementation, reported patient compliance and referrals to multidisciplinary specialists increased from 72.9% to 81.30% and 21.2% to 56.20%, respectively. Repeat ED visits for stone-related encounters within 6 months of initial presentation remained relatively stable (from 17.60% to 18.9%), while no-show rates at first follow-up decreased from 20.0% to 6.30% by study conclusion. There is continued supporting evidence for the importance of a comprehensive kidney stone program specifically for patients of lower socioeconomic status following a 3-year implementation at our institution. Encouraging results indicate increased access to multidisciplinary specialty referrals, with improvement in follow-up and reported compliance related to stone prevention strategies.

Expression and function of human ribonuclease 4 in the kidney and urinary tract.

Antimicrobial peptides are essential host defense mechanisms that prevent urinary tract infections. Recent studies have demonstrated that peptides in the ribonuclease A superfamily have antimicrobial activity against uropathogens and protect the urinary tract from uropathogenic Escherichia coli (UPEC). Little is known about the antibacterial function or expression of ribonuclease 4 (RNase 4) in the human urinary tract. Here, we show that full-length recombinant RNase 4 peptide and synthetic amino-terminal RNase 4 peptide fragment have antibacterial activity against UPEC and multidrug-resistant (MDR)-UPEC. RNASE4 transcript expression was detected in human kidney and bladder tissue using quantitative real-time PCR. Immunostaining or in situ hybridization localized RNase 4 expression to proximal tubules, principal and intercalated cells in the kidney's collecting duct, and the bladder urothelium. Urinary RNase 4 concentrations were quantified in healthy controls and females with a history of urinary tract infection. Compared with controls, urinary RNase 4 concentrations were significantly lower in females with a history of urinary tract infection. When RNase 4 was neutralized in human urine or silenced in vitro using siRNA, urinary UPEC replication or attachment to and invasion of urothelial and kidney medullary cells increased. These data show that RNase 4 has antibacterial activity against UPEC, is expressed in the human urinary tract, and can contribute to host defense against urinary tract infections.NEW & NOTEWORTHY Ribonuclease 4 (RNase 4) is a newly identified host defense peptide in the human kidney and bladder. RNase 4 kills uropathogenic Escherichia coli (UPEC) and multidrug-resistant UPEC. RNase 4 prevents invasive UPEC infection and suppressed RNase 4 expression may be a risk factor for more severe or recurrent urinary tract infection.

Ribonuclease 7 Shields the Kidney and Bladder from Invasive Uropathogenic Escherichia coli Infection.

BACKGROUND: Evidence suggests that antimicrobial peptides, components of the innate immune response, protect the kidneys and bladder from bacterial challenge. We previously identified ribonuclease 7 (RNase 7) as a human antimicrobial peptide that has bactericidal activity against uropathogenic Escherichia coli (UPEC). Functional studies assessing RNase 7's contributions to urinary tract defense are limited. METHODS: To investigate RNase 7's role in preventing urinary tract infection (UTI), we quantified urinary RNase 7 concentrations in 29 girls and adolescents with a UTI history and 29 healthy female human controls. To assess RNase 7's antimicrobial activity in vitro in human urothelial cells, we used siRNA to silence urothelial RNase 7 production and retroviral constructs to stably overexpress RNase 7; we then evaluated UPEC's ability to bind and invade these cells. For RNase 7 in vivo studies, we developed humanized RNase 7 transgenic mice, subjected them to experimental UTI, and enumerated UPEC burden in the urine, bladder, and kidneys. RESULTS: Compared with controls, study participants with a UTI history had 1.5-fold lower urinary RNase 7 concentrations. When RNase 7 was silenced in vitro, the percentage of UPEC binding or invading human urothelial cells increased; when cells overexpressed RNase 7, UPEC attachment and invasion decreased. In the transgenic mice, we detected RNase 7 expression in the kidney's intercalated cells and bladder urothelium. RNase 7 humanized mice exhibited marked protection from UPEC. CONCLUSIONS: These findings provide evidence that RNase 7 has a role in kidney and bladder host defense against UPEC and establish a foundation for investigating RNase 7 as a UTI prognostic marker or nonantibiotic-based therapy.

Insulin receptor signaling regulates renal collecting duct and intercalated cell antibacterial defenses.

People with diabetes mellitus have increased infection risk. With diabetes, urinary tract infection (UTI) is more common and has worse outcomes. Here, we investigate how diabetes and insulin resistance impact the kidney's innate defenses and urine sterility. We report that type 2 diabetic mice have increased UTI risk. Moreover, insulin-resistant prediabetic mice have increased UTI susceptibility, independent of hyperglycemia or glucosuria. To identify how insulin resistance affects renal antimicrobial defenses, we genetically deleted the insulin receptor in the kidney's collecting tubules and intercalated cells. Intercalated cells, located within collecting tubules, contribute to epithelial defenses by acidifying the urine and secreting antimicrobial peptides (AMPs) into the urinary stream. Collecting duct and intercalated cell-specific insulin receptor deletion did not impact urine acidification, suppressed downstream insulin-mediated targets and AMP expression, and increased UTI susceptibility. Specifically, insulin receptor-mediated signaling regulates AMPs, including lipocalin 2 and ribonuclease 4, via phosphatidylinositol-3-kinase signaling. These data suggest that insulin signaling plays a critical role in renal antibacterial defenses.

Histone H1 depletion triggers an interferon response in cancer cells via activation of heterochromatic repeats.

Histone H1 has seven variants in human somatic cells and contributes to chromatin compaction and transcriptional regulation. Knock-down (KD) of each H1 variant in breast cancer cells results in altered gene expression and proliferation differently in a variant specific manner with H1.2 and H1.4 KDs being most deleterious. Here we show combined depletion of H1.2 and H1.4 has a strong deleterious effect resulting in a strong interferon (IFN) response, as evidenced by an up-regulation of many IFN-stimulated genes (ISGs) not seen in individual nor in other combinations of H1 variant KDs. Although H1 participates to repress ISG promoters, IFN activation upon H1.2 and H1.4 KD is mainly generated through the activation of the IFN response by cytosolic nucleic acid receptors and IFN synthesis, and without changes in histone modifications at induced ISG promoters. H1.2 and H1.4 co-KD also promotes the appearance of accessibility sites genome wide and, particularly, at satellites and other repeats. The IFN response may be triggered by the expression of noncoding RNA generated from heterochromatic repeats or endogenous retroviruses upon H1 KD. In conclusion, redundant H1-mediated silencing of heterochromatin is important to maintain cell homeostasis and to avoid an unspecific IFN response.

Extraordinary Cancer Epigenomics: Thinking Outside the Classical Coding and Promoter Box.

The advent of functional genomics powered by high-throughput sequencing has given us a new appreciation of the genomic sequences that lie outside the canonical promoter-coding sequence box. These regions harbor distant regulatory elements, enhancers, super-enhancers, insulators, alternative promoters, and sequences that transcribe as noncoding RNAs (ncRNAs) such as miRNAs and long ncRNAs. These functional genomics studies have also enabled a clearer understanding of the role of the 3D structure of the genome in epigenetic regulation. Here we review the impact that epigenetic changes, and specifically DNA methylation, have on these extraordinary sequences in driving cancer progression.

Comparative FAIRE-seq analysis reveals distinguishing features of the chromatin structure of ground state- and primed-pluripotent cells.

Both pluripotent embryonic stem cells (ESCs), established from preimplantation murine blastocysts, and epiblast stem cells (EpiSCs), established from postimplantation embryos, can self-renew in culture or differentiate into each of the primary germ layers. While the core transcription factors (TFs) OCT4, SOX2, and NANOG are expressed in both cell types, the gene expression profiles and other features suggest that ESCs and EpiSCs reflect distinct developmental maturation stages of the epiblast in vivo. Accordingly, "naïve" or "ground state" ESCs resemble cells of the inner cell mass, whereas "primed" EpiSCs resemble cells of the postimplantation egg cylinder. To gain insight into the relationship between naïve and primed pluripotent cells, and of each of these pluripotent states to that of nonpluripotent cells, we have used FAIRE-seq to generate a comparative atlas of the accessible chromatin regions within ESCs, EpiSCs, multipotent neural stem cells, and mouse embryonic fibroblasts. We find a distinction between the accessible chromatin patterns of pluripotent and somatic cells that is consistent with the highly related phenotype of ESCs and EpiSCs. However, by defining cell-specific and shared regions of open chromatin, and integrating these data with published gene expression and ChIP analyses, we also illustrate unique features of the chromatin of naïve and primed cells. Functional studies suggest that multiple stage-specific enhancers regulate ESC- or EpiSC-specific gene expression, and implicate auxiliary TFs as important modulators for stage-specific activation by the core TFs. Together these observations provide insights into the chromatin structure dynamics accompanying transitions between these pluripotent states.

FIREWACh: high-throughput functional detection of transcriptional regulatory modules in mammalian cells.

Promoters and enhancers establish precise gene transcription patterns. The development of functional approaches for their identification in mammalian cells has been complicated by the size of these genomes. Here we report a high-throughput functional assay for directly identifying active promoter and enhancer elements called FIREWACh (Functional Identification of Regulatory Elements Within Accessible Chromatin), which we used to simultaneously assess over 80,000 DNA fragments derived from nucleosome-free regions within the chromatin of embryonic stem cells (ESCs) and identify 6,364 active regulatory elements. Many of these represent newly discovered ESC-specific enhancers, showing enriched binding-site motifs for ESC-specific transcription factors including SOX2, POU5F1 (OCT4) and KLF4. The application of FIREWACh to additional cultured cell types will facilitate functional annotation of the genome and expand our view of transcriptional network dynamics.

Systemic delivery of MeCP2 rescues behavioral and cellular deficits in female mouse models of Rett syndrome.

De novo mutations in the X-linked gene encoding the transcription factor methyl-CpG binding protein 2 (MECP2) are the most frequent cause of the neurological disorder Rett syndrome (RTT). Hemizygous males usually die of neonatal encephalopathy. Heterozygous females survive into adulthood but exhibit severe symptoms including microcephaly, loss of purposeful hand motions and speech, and motor abnormalities, which appear after a period of apparently normal development. Most studies have focused on male mouse models because of the shorter latency to and severity in symptoms, yet how well these mice mimic the disease in affected females is not clear. Very few therapeutic treatments have been proposed for females, the more gender-appropriate model. Here, we show that self-complementary AAV9, bearing MeCP2 cDNA under control of a fragment of its own promoter (scAAV9/MeCP2), is capable of significantly stabilizing or reversing symptoms when administered systemically into female RTT mice. To our knowledge, this is the first potential gene therapy for females afflicted with RTT.

Isolation and analysis of DNA derived from nucleosome-free regions.

Precise regulation of the levels and timing of gene expression is fundamental to all biological processes and is largely determined by the activity of cis-regulatory modules, containing the binding sites for transcription factors, within promoters and enhancers. The global identification of these transcriptional regulatory elements within mammalian genomes, and understanding when and where they are active, is an important effort that will require the development and implementation of several different technologies. Here we detail a means for the identification of transcriptional regulatory elements using functional assays. The success of this approach relies on focusing the functional assay on DNA derived from nucleosome-free regions (NFRs), i.e., the 2% of the genome within a given cell in which regulatory elements reside. Accordingly, we present a simple method for isolating NFR DNA, and a functional assay that can be used for the identification of promoter and enhancers components within this population.

Astrocytes from familial and sporadic ALS patients are toxic to motor neurons.

Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease, with astrocytes implicated as contributing substantially to motor neuron death in familial (F)ALS. However, the proposed role of astrocytes in the pathology of ALS derives in part from rodent models of FALS based upon dominant mutations within the superoxide dismutase 1 (SOD1) gene, which account for <2% of all ALS cases. Their role in sporadic (S)ALS, which affects >90% of ALS patients, remains to be established. Using astrocytes generated from postmortem tissue from both FALS and SALS patients, we show that astrocytes derived from both patient groups are similarly toxic to motor neurons. We also demonstrate that SOD1 is a viable target for SALS, as its knockdown significantly attenuates astrocyte-mediated toxicity toward motor neurons. Our data highlight astrocytes as a non-cell autonomous component in SALS and provide an in vitro model system to investigate common disease mechanisms and evaluate potential therapies for SALS and FALS.

Rapid and efficient generation of functional motor neurons from human pluripotent stem cells using gene delivered transcription factor codes.

Stem cell-derived motor neurons (MNs) are increasingly utilized for modeling disease in vitro and for developing cellular replacement strategies for spinal cord injury and diseases such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Human embryonic stem cell (hESC) differentiation into MNs, which involves retinoic acid (RA) and activation of the sonic hedgehog (SHH) pathway is inefficient and requires up to 60 days to develop MNs with electrophysiological properties. This prolonged differentiation process has hampered the use of hESCs, in particular for high-throughput screening. We evaluated the MN gene expression profile of RA/SHH-differentiated hESCs to identify rate-limiting factors involved in MN development. Based on this analysis, we developed an adenoviral gene delivery system encoding for MN inducing transcription factors: neurogenin 2 (Ngn2), islet-1 (Isl-1), and LIM/homeobox protein 3 (Lhx3). Strikingly, delivery of these factors induced functional MNs with mature electrophysiological properties, 11-days after gene delivery, with >60-70% efficiency from hESCs and human induced pluripotent stem cells (hiPSCs). This directed programming approach significantly reduces the time required to generate electrophysiologically-active MNs by approximately 30 days in comparison to conventional differentiation techniques. Our results further exemplify the potential to use transcriptional coding for rapid and efficient production of defined cell types from hESCs and hiPSCs.

Directed evolution of adeno-associated virus to an infectious respiratory virus.

Respiratory viruses evolve to maintain infectivity levels that permit spread yet prevent host and virus extinction, resulting in surprisingly low infection rates. Respiratory viruses harnessed as gene therapy vectors have illustrated this limitation. We used directed evolution in an organotypic human airway model to generate a highly infectious adeno-associated virus. This virus mediated gene transfer more than 100-fold better than parental strains and corrected the cystic fibrosis epithelial Cl(-) transport defect. Thus, under appropriate selective pressures, viruses can evolve to be more infectious than observed in nature, a finding that holds significant implications for designing vectors for gene therapy and for understanding emerging pathogens.

Cyclodextrin retinylidene: a biomimetic kinetic trap model for rhodopsin.

All trans retinal was attached to both the primary face and the secondary face of beta-cyclodextrin via a Schiff base linkage, analogous to that in rhodopsin. The new models were evaluated and compared with n-butylamine retinylidene Schiff base for their rates of hydrolysis, and factors that influence such rates. Competition studies using adamantane carboxylate demonstrated the kinetic trap theory by diminishing the binding of retinal in the cyclodextrin, thereby augmenting the rate of hydrolysis. NMR experiments indicate that the retinylidene is most probably bound in the form of a dimer.