Patient Satisfaction With Long-term Sacral Neuromodulation for Fecal Incontinence: Experience from a Single Tertiary Center.

BACKGROUND: Sacral Neuromodulation is an effective treatment for faecal incontinence in the long-term. Efficacy is typically assessed using bowel diary, symptom severity, or quality of life questionnaires and 'success' defined as >50% improvement in these measures. Patient satisfaction may however be a more meaningful and individualised measure of treatment efficacy. OBJECTIVE: To assess patient reported satisfaction with long-term sacral neuromodulation and compare it to the frequently applied efficacy measures. DESIGN: An observational study of a prospectively maintained database. SETTING: A single tertiary pelvic floor referral unit. PATIENTS: Data from 70 (68 female, median age 69 [60 - 74]) patients were available. The median time since implantation was 11 (9 - 14) years. Nineteen patients reported inactive neuromodulation devices. MAIN OUTCOME MEASURES: Bowel diaries, the Manchester Health Questionnaire, and the St Marks Incontinence Score recorded at baseline, after percutaneous nerve evaluation, and at last follow-up. Patient reported satisfaction, using a 0%-100% visual analogue scale, with treatment since implantation (overall) and in the two-weeks preceding completion of the last outcome measures (current). RESULTS: Satisfaction was significantly higher in those with active sacral neuromodulation devices (75% vs 20%, p<0.001) at follow-up. No significant relationships exist between symptom improvement using conventional measures, and patient reported satisfaction. Current satisfaction was not associated with changes in bowel diary data following percutaneous nerve evaluation. Despite improvements in the St Mark's incontinence score and Manchester Health Questionnaire below the 50% improvement threshold used to define 'success', patients reported high (80%) satisfaction. LIMITATIONS: Retrospective with gaps in the available data. CONCLUSIONS: High patient satisfaction with sacral neuromodulation can be achieved, however the response to percutaneous nerve evaluation may not predict treatment satisfaction in long-term. The change in questionnaire results, which measure the use of compensatory behaviors and quality of life impact, may better correspond to treatment satisfaction.

A comparison of function lumen imaging probe measurements of anal sphincter function in fecal incontinence.

BACKGROUND: The functional lumen imaging probe (FLIP) is a test of anal sphincter distensibility under evaluation by specialist centers. Two measurement protocols termed "stepwise" and "ramp" are used, risking a lack of standardization. This study aims to compare the performance of these protocols to establish if there are differences between them. METHODS: Patients with fecal incontinence were recruited and underwent measurement with both protocols at a tertiary pelvic floor referral unit. Differences in minimum diameter, FLIP bag pressure, and distensibility index (DI) at rest and during squeeze were calculated at various FLIP bag volumes. KEY RESULTS: Twenty patients (19 female, mean age 61 [range: 38-78]) were included. The resting minimum diameter at 30 and 40 mL bag volumes were less in the stepwise protocol (mean bias: -0.55 mm and -1.18 mm, p < 0.05) along with the DI at the same bag volumes (mean bias: -0.37 mm2/mmHg and -0.55 mm2/mmHg, p < 0.05). There was also a trend towards greater bag pressures at 30 mL (mean bias: +2.08 mmHg, p = 0.114) and 40 mL (mean bias: +2.81 mmHg, p = 0.129) volumes in the stepwise protocol. There were no differences between protocols in measurements of minimum diameter, maximum bag pressure, or DI during voluntary squeeze (p > 0.05). CONCLUSION AND INFERENCES: There are differences between the two commonly described FLIP measurement protocols at rest, although there are no differences in the assessment of squeeze function. Consensus agreement is required to agree the most appropriate FLIP measurement protocol in assessing anal sphincter function.

Percutaneous tibial nerve stimulation versus sacral nerve stimulation for the treatment of faecal incontinence.

Introduction: Faecal incontinence (FI) is a common condition with a significant impact on quality of life (QoL). Neuromodulation treatments delivered by members of the multidisciplinary team including sacral nerve stimulation (SNS) and percutaneous tibial nerve stimulation (PTNS) are options for FI refractory to conservative management. The aim of this study was to assess whether a successful treatment with one neuromodulation modality corresponds with success in the other. Methods: A retrospective review of a prospectively managed neuromodulation database identified 15 patients who had undergone both PTNS and SNS. The definition of success of each treatment was a >50% improvement in any of The St. Mark's Incontinence Score, Manchester Health Questionnaire, or weekly faecal urgency or FI episodes. Results: Complete data from 12 patients was available for assessment and PTNS was delivered as the first treatment in nine patients. Overall, seven patients (58%) had successful PTNS treatment, with 10 (83%) having a successful SNS trials. Of the seven patients who had successful PTNS treatment, six patients (85.4%) went on to have success with SNS. Of the five patients who failed PTNS, four (80%) went on to have SNS success. Five (71%) of those who had positive PTNS outcomes had permanent SNS implantation as their final treatment decision. Conclusion: This study suggests that there is no clear relationship between successful PTNS treatment and an SNS trial period which may be explained by differing mechanisms of action or the potential placebo effect of PTNS. Further work is required to investigate any association in larger studies to inform clinical practice.

Production and secretion of recombinant spider silk in Bacillus megaterium.

BACKGROUND: Silk proteins have emerged as versatile biomaterials with unique chemical and physical properties, making them appealing for various applications. Among them, spider silk, known for its exceptional mechanical strength, has attracted considerable attention. Recombinant production of spider silk represents the most promising route towards its scaled production; however, challenges persist within the upstream optimization of host organisms, including toxicity and low yields. The high cost of downstream cell lysis and protein purification is an additional barrier preventing the widespread production and use of spider silk proteins. Gram-positive bacteria represent an attractive, but underexplored, microbial chassis that may enable a reduction in the cost and difficulty of recombinant silk production through attributes that include, superior secretory capabilities, frequent GRAS status, and previously established use in industry. RESULTS: In this study, we explore the potential of gram-positive hosts by engineering the first production and secretion of recombinant spider silk in the Bacillus genus. Using an industrially relevant B. megaterium host, it was found that the Sec secretion pathway enables secretory production of silk, however, the choice of signal sequence plays a vital role in successful secretion. Attempts at increasing secreted titers revealed that multiple translation initiation sites in tandem do not significantly impact silk production levels, contrary to previous findings for other gram-positive hosts and recombinant proteins. Notwithstanding, targeted amino acid supplementation in minimal media was found to increase production by 135% relative to both rich media and unaltered minimal media, yielding secretory titers of approximately 100 mg/L in flask cultures. CONCLUSION: It is hypothesized that the supplementation strategy addressed metabolic bottlenecks, specifically depletion of ATP and NADPH within the central metabolism, that were previously observed for an E. coli host producing the same recombinant silk construct. Furthermore, this study supports the hypothesis that secretion mitigates the toxicity of the produced silk protein on the host organism and enhances host performance in glucose-based minimal media. While promising, future research is warranted to understand metabolic changes more precisely in the Bacillus host system in response to silk production, optimize signal sequences and promoter strengths, investigate the mechanisms behind the effect of tandem translation initiation sites, and evaluate the performance of this system within a bioreactor.

The Long-term Outcomes of Sacral Neuromodulation for Fecal Incontinence: A Single-Center Experience.

BACKGROUND: Sacral neuromodulation is an effective treatment for fecal incontinence. OBJECTIVE: To assess the long-term outcomes of sacral neuromodulation and establish the outcomes of patients with inactive devices. DESIGN: This is an observational study of patients treated for >5 years. A positive outcome was defined as a more than 50% reduction in fecal incontinence episodes or improvement in a symptom severity score. Data were reviewed from a prospectively managed database. SETTINGS: This study was conducted at a single tertiary referral center. PATIENTS: Data from 74 patients (72 women) were available at long-term follow-up. MAIN OUTCOME MEASURES: Bowel diary, St. Mark's incontinence score, and Manchester Health Questionnaire data were prospectively recorded at baseline, after percutaneous nerve evaluation, and at last follow-up. RESULTS: Patients were analyzed in cohorts based on time since sacral neuromodulation implantation: group 1: 5 to 10 years (n = 20), group 2: >10 years (n = 35), and group 3: inactive sacral neuromodulation devices (n = 19). Median St. Mark's incontinence score and Manchester Health Questionnaire improved from baseline to last follow-up in group 1 ( p ≤ 0.05) and group 2 ( p ≤ 0.05), but in group 3, results returned to baseline levels at the last follow-up. Similarly, weekly fecal incontinence episodes improved in both active device groups at the last follow-up. However, in group 3, incontinence episodes were no different from baseline ( p = 0.722). Despite active devices, fecal urgency episodes increased at the last follow-up after >10 years since percutaneous nerve evaluation ( p ≤ 0.05). Complete continence was reported by 44% of patients, and at least a 50% improvement was seen in 77% of patients with active devices. LIMITATIONS: This study is retrospective with some gaps in the available data at the last follow-up. CONCLUSIONS: Sacral neuromodulation is an effective treatment for fecal incontinence in the long term, but all outcomes are adversely affected by device inactivity. Therefore, ongoing stimulation is required for continued benefit. See Video Abstract. RESULTADOS A LARGO PLAZO DE LA NEUROMODULACIN SACRA PARA LA INCONTINENCIA FECAL EXPERIENCIA DE UN SOLO CENTRO: ANTECEDENTES:La neuromodulación sacra es un tratamiento eficaz para la incontinencia fecal.OBJETIVO:Este estudio tuvo como objetivo evaluar los resultados a largo plazo de la neuromodulación sacra y establecer los resultados de los pacientes con dispositivos inactivos.DISEÑO:Este es un estudio observacional de pacientes tratados durante más de 5 años. Un resultado positivo se definió como una reducción >50 % en los episodios de incontinencia fecal o una mejoría en la puntuación de gravedad de los síntomas. Los datos se revisaron a partir de una base de datos administrada prospectivamente.ENTERNO CLINICO:Este estudio se realizó en un solo centro de referencia terciario.PACIENTES:Los datos de 74 pacientes (72 mujeres) estaban disponibles en el seguimiento a largo plazo.PRINCIPALES MEDIDAS DE RESULTADO:Diario intestinal, puntuación de incontinencia de St. Mark y datos del Cuestionario de salud de Manchester se registraron prospectivamente al inicio, después de la evaluación de nervio periférico y en el último seguimiento.RESULTADOS:Los pacientes se analizaron en cohortes según el tiempo transcurrido desde la implantación de la neuromodulación sacra: Grupo 1: 5-10 años (n = 20), Grupo 2: >10 años (n = 35) y Grupo 3: dispositivos SNM inactivos (n = 19). La mediana de la puntuación de incontinencia de St. Mark y Questionnaire Cuestionario de salud de Manchester mejoraron desde el inicio hasta el último seguimiento en el Grupo 1 (p = < 0,05) y el Grupo 2 (p = < 0,05), pero en el Grupo 3 los resultados volvieron a los niveles iniciales en el último seguimiento. arriba. De manera similar, los episodios semanales de incontinencia fecal mejoraron en ambos grupos de dispositivos activos en el último seguimiento. Sin embargo, en el Grupo 3 los episodios de incontinencia no fueron diferentes de los basales (p = 0,722). A pesar de los dispositivos activos, los episodios de urgencia fecal aumentaron en el último seguimiento después de más de 10 años desde la evaluación del nervio periférico (p = < 0,05). Continencia completa se reportó en el 44 % de los pacientes, y al menos una mejora del 50 % en el 77 % con dispositivos activos.LIMITACIONES:Este estudio es retrospectivo con algunas vacíos en los datos disponibles en el último seguimiento.CONCLUSIONES:La neuromodulación sacra es un tratamiento eficaz para la incontinencia fecal a largo plazo, pero todos los resultados se ven afectados negativamente por la inactividad del dispositivo. Por lo tanto, se requiere estimulación continua para un beneficio continuo. (Traducción- Dr. Francisco M. Abarca-Rendon ).

Two-step conversion of polyethylene into recombinant proteins using a microbial platform.

BACKGROUND: The increasing prevalence of plastic waste combined with the inefficiencies of mechanical recycling has inspired interest in processes that can convert these waste streams into value-added biomaterials. To date, the microbial conversion of plastic substrates into biomaterials has been predominantly limited to polyhydroxyalkanoates production. Expanding the capabilities of these microbial conversion platforms to include a greater diversity of products generated from plastic waste streams can serve to promote the adoption of these technologies at a larger scale and encourage a more sustainable materials economy. RESULTS: Herein, we report the development of a new strain of Pseudomonas bacteria capable of converting depolymerized polyethylene into high value bespoke recombinant protein products. Using hexadecane, a proxy for depolymerized polyethylene, as a sole carbon nutrient source, we optimized media compositions that facilitate robust biomass growth above 1 × 109 cfu/ml, with results suggesting the benefits of lower hydrocarbon concentrations and the use of NH4Cl as a nitrogen source. We genomically integrated recombinant genes for green fluorescent protein and spider dragline-inspired silk protein, and we showed their expression in Pseudomonas aeruginosa, reaching titers of approximately 10 mg/L when hexadecane was used as the sole carbon source. Lastly, we demonstrated that chemically depolymerized polyethylene, comprised of a mixture of branched and unbranched alkanes, could be converted into silk protein by Pseudomonas aeruginosa at titers of 11.3 ± 1.1 mg/L. CONCLUSION: This work demonstrates a microbial platform for the conversion of a both alkanes and plastic-derived substrates to recombinant, protein-based materials. The findings in this work can serve as a basis for future endeavors seeking to upcycle recalcitrant plastic wastes into value-added recombinant proteins.

A Suicide Prevention Intervention for Emerging Adult Sexual and Gender Minority Groups: Protocol for a Pilot Hybrid Effectiveness Randomized Controlled Trial.

BACKGROUND: Suicide attempts and suicide death disproportionately affect sexual and gender minority emerging adults (age 18-24 years). However, suicide prevention strategies tailored for emerging adult sexual and gender minority (EA-SGM) groups are not widely available. The Safety Planning Intervention (SPI) has strong evidence for reducing the risk for suicide in the general population, but it is unclear how best to support EA-SGM groups in their use of a safety plan. Our intervention (Supporting Transitions to Adulthood and Reducing Suicide [STARS]) builds on content from an existing life skills mobile app for adolescent men who have sex with men (iREACH) and seeks to target core risk factors for suicide among EA-SGM groups, namely, positive affect, discrimination, and social disconnection. The mobile app is delivered to participants randomized to STARS alongside 6 peer mentoring sessions to support the use of the safety plan and other life skills from the app to ultimately reduce suicide risk. OBJECTIVE: We will pilot-test the combination of peer mentoring alongside an app-based intervention (STARS) designed to reduce suicidal ideation and behaviors. STARS will include suicide prevention content and will target positive affect, discrimination, and social support. After an in-person SPI with a clinician, STARS users can access content and activities to increase their intention to use SPI and overcome obstacles to its use. EA-SGM groups will be randomized to receive either SPI alone or STARS and will be assessed for 6 months. METHODS: Guided by the RE-AIM (reach, efficacy, adoption, implementation, and maintenance) framework, we will recruit and enroll a racially and ethnically diverse sample of 60 EA-SGM individuals reporting past-month suicidal ideation. Using a type-1 effectiveness-implementation hybrid design, participants will be randomized to receive SPI (control arm) or to receive SPI alongside STARS (intervention arm). We will follow the participants for 6 months, with evaluations at 2, 4, and 6 months. Preliminary effectiveness outcomes (suicidal ideation and behavior) and hypothesized mechanisms of change (positive affect, coping with discrimination, and social support) will serve as our primary outcomes. Secondary outcomes include key implementation indicators, including participants' willingness and adoption of SPI and STARS and staff's experiences with delivering the program. RESULTS: Study activities began in September 2021 and are ongoing. The study was approved by the institutional review board of the University of Pennsylvania (protocol number 849500). Study recruitment began on October 14, 2022. CONCLUSIONS: This project will be among the first tailored, mobile-based interventions for EA-SGM groups at risk for suicide. This project is responsive to the documented gaps for this population: approaches that address chosen family, focus on a life-course perspective, web approaches, and focus on health equity and provision of additional services relevant to sexual and gender minority youth. TRIAL REGISTRATION: ClinicalTrials.gov NCT05018143; https://classic.clinicaltrials.gov/ct2/show/NCT05018143. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/48177.

Silk fibroin production in Escherichia coli is limited by a positive feedback loop between metabolic burden and toxicity stress.

To investigate the metabolic elasticity and production bottlenecks for recombinant silk proteins in Escherichia coli, we performed a comprehensive characterization of one elastin-like peptide strain (ELP) and two silk protein strains (A5 4mer, A5 16mer). Our approach included 13C metabolic flux analysis, genome-scale modeling, transcription analysis, and 13C-assisted media optimization experiments. Three engineered strains maintained their central flux network during growth, while measurable metabolic flux redistributions (such as the Entner-Doudoroff pathway) were detected. Under metabolic burdens, the reduced TCA fluxes forced the engineered strain to rely more on substrate-level phosphorylation for ATP production, which increased acetate overflow. Acetate (as low as 10 mM) in the media was highly toxic to silk-producing strains, which reduced 4mer production by 43% and 16mer by 84%, respectively. Due to the high toxicity of large-size silk proteins, 16mer's productivity was limited, particularly in the minimal medium. Therefore, metabolic burden, overflow acetate, and toxicity of silk proteins may form a vicious positive feedback loop that fractures the metabolic network. Three solutions could be applied: 1) addition of building block supplements (i.e., eight key amino acids: His, Ile, Phe, Pro, Tyr, Lys, Met, Glu) to reduce metabolic burden; 2) disengagement of growth and production; and 3) use of non-glucose based substrate to reduce acetate overflow. Other reported strategies were also discussed in light of decoupling this positive feedback loop.

Novel insights into construct toxicity, strain optimization, and primary sequence design for producing recombinant silk fibroin and elastin-like peptide in E. coli.

Spider silk proteins (spidroins) are a remarkable class of biomaterials that exhibit a unique combination of high-value attributes and can be processed into numerous morphologies for targeted applications in diverse fields. Recombinant production of spidroins represents the most promising route towards establishing the industrial production of the material, however, recombinant spider silk production suffers from fundamental difficulties that includes low titers, plasmid instability, and translational inefficiencies. In this work, we sought to gain a deeper understanding of upstream bottlenecks that exist in the field through the production of a panel of systematically varied spidroin sequences in multiple E. coli strains. A restriction on basal expression and specific genetic mutations related to stress responses were identified as primary factors that facilitated higher titers of the recombinant silk constructs. Using these findings, a novel strain of E. coli was created that produces recombinant silk constructs at levels 4-33 times higher than standard BL21(DE3). However, these findings did not extend to a similar recombinant protein, an elastin-like peptide. It was found that the recombinant silk proteins, but not the elastin-like peptide, exert toxicity on the E. coli host system, possibly through their high degree of intrinsic disorder. Along with strain engineering, a bioprocess design that utilizes longer culturing times and attenuated induction was found to raise recombinant silk titers by seven-fold and mitigate toxicity. Targeted alteration to the primary sequence of the recombinant silk constructs was also found to mitigate toxicity. These findings identify multiple points of focus for future work seeking to further optimize the recombinant production of silk proteins and is the first work to identify the intrinsic disorder and subsequent toxicity of certain spidroin constructs as a primary factor related to the difficulties of production.

Current and future perspectives on the utility of provocative tests of anal sphincter function: A state-of-the-art summary.

BACKGROUND: The maintenance of fecal continence depends upon coordinated interactions between the pelvic floor, anorectum, and anal sphincter complex orchestrated by central and peripheral neural activities. The current techniques to objectively measure anorectal function rely on fixed diameter catheters placed inside the anal canal with a rectal balloon to obtain measurements of anal resting and squeeze function, and rectal compliance. Until recently it had not been possible to measure the distensibility of the anal canal, or in other words its ability to resist opening against an increasing pressure, which has been proposed as the main determinant of a biological sphincter's function. Anal acoustic reflectometry (AAR) and the functional lumen imaging probe (FLIP) are two novel, provocative techniques that dynamically assess the anal sphincter complex under volume-controlled distension. In doing so, both provide information on the viscoelastic properties of the anal canal and offer new insights into its function. PURPOSE: This review details the current and potential future applications of AAR and FLIP and highlights the unanswered questions relevant to these new technologies.

Bioproduction of biomacromolecules for antiviral applications.

The societal damage brought on by viral epidemics indicates that next-generation antiviral treatments must be developed and deployed. Biomacromolecules are a diverse class of compounds that can potentially exhibit potent antiviral activity. Their efficacy and mechanisms of action are dependent upon multiple structural factors, including molecular weight, degree and position of sulfation, and backbone stereochemistry. Extracting biomacromolecules from animals and plants for healthcare applications is undesirable, as these methods are unable to yield products with well-defined chemical structures. Modern advances utilizing recombinant microbes and metabolic pathway engineering can be a key step towards large-scale bioproduction of tailored biomacromolecules for targeted antiviral applications.

Chemical Synthesis of Silk-Mimetic Polymers.

Silk is a naturally occurring high-performance material that can surpass man-made polymers in toughness and strength. The remarkable mechanical properties of silk result from the primary sequence of silk fibroin, which bears semblance to a linear segmented copolymer with alternating rigid ("crystalline") and flexible ("amorphous") blocks. Silk-mimetic polymers are therefore of great emerging interest, as they can potentially exhibit the advantageous features of natural silk while possessing synthetic flexibility as well as non-natural compositions. This review describes the relationships between primary sequence and material properties in natural silk fibroin and furthermore discusses chemical approaches towards the synthesis of silk-mimetic polymers. In particular, step-growth polymerization, controlled radical polymerization, and copolymerization with naturally derived silk fibroin are presented as strategies for synthesizing silk-mimetic polymers with varying molecular weights and degrees of sequence control. Strategies for improving macromolecular solubility during polymerization are also highlighted. Lastly, the relationships between synthetic approach, supramolecular structure, and bulk material properties are explored in this review, with the aim of providing an informative perspective on the challenges facing chemical synthesis of silk-mimetic polymers with desirable properties.

Do Stereotypic Images in Video Games Affect Attitudes and Behavior? Adolescents' Perspectives.

This study examined adolescents' attitudes about video games along with their self-reported play frequency. Ninth and eleventh grade students (N = 361), approximately evenly divided by grade and gender, were surveyed about whether video games have stereotypic images, involve harmful consequences or affect one's attitudes, whether game playing should be regulated by parents or the government, and whether game playing is a personal choice. Adolescents who played video games frequently showed decreased concern about the effects that games with negatively stereotyped images may have on the players' attitudes compared to adolescents who played games infrequently or not at all. With age, adolescents were more likely to view images as negative, but were also less likely to recognize stereotypic images of females as harmful and more likely to judge video-game playing as a personal choice. The paper discusses other findings in relation to research on adolescents' social cognitive judgments.

Social Evaluations of Stereotypic Images in Video Games: Unfair, Legitimate, or "Just Entertainment"?

The aim of this study was to assess adolescents' evaluations of, and reasoning about, gender stereotypes in video games. Female (N = 46) and male (N = 41), predominantly European-American, mean age = 19 years, were interviewed about their knowledge of game usage, awareness and evaluation of stereotypes, beliefs about the influences of games on the players, and authority jurisdiction over 3 different types of games: games with negative male stereotypes, and games with negative female stereotypes, and gender-neutral games. Gender differences were found for how participants evaluated these games. Males were more likely than females to find stereotypes acceptable. Results are discussed in terms of social reasoning, video game playing, and gender differences.