A Minimal PBPK/PD Model with Expansion-Enhanced Target-Mediated Drug Disposition to Support a First-in-Human Clinical Study Design for a FLT3L-Fc Molecule.

FLT3L-Fc is a half-life extended, effectorless Fc-fusion of the native human FLT3-ligand. In cynomolgus monkeys, treatment with FLT3L-Fc leads to a complex pharmacokinetic/pharmacodynamic (PK/PD) relationship, with observed nonlinear PK and expansion of different immune cell types across different dose levels. A minimal physiologically based PK/PD model with expansion-enhanced target-mediated drug disposition (TMDD) was developed to integrate the molecule's mechanism of action, as well as the complex preclinical and clinical PK/PD data, to support the preclinical-to-clinical translation of FLT3L-Fc. In addition to the preclinical PK data of FLT3L-Fc in cynomolgus monkeys, clinical PK and PD data from other FLT3-agonist molecules (GS-3583 and CDX-301) were used to inform the model and project the expansion profiles of conventional DC1s (cDC1s) and total DCs in peripheral blood. This work constitutes an essential part of our model-informed drug development (MIDD) strategy for clinical development of FLT3L-Fc by projecting PK/PD in healthy volunteers, determining the first-in-human (FIH) dose, and informing the efficacious dose in clinical settings. Model-generated results were incorporated in regulatory filings to support the rationale for the FIH dose selection.

Multi-Institutional Bladder Exstrophy Consortium After 8 Years: The Short- and Intermediate-Term Outcomes.

PURPOSE: Bladder exstrophy (BE) poses challenges both during the surgical repair and throughout follow-up. In 2013, a multi-institutional BE consortium was initiated, which included utilization of unified surgical principles for the complete primary repair of exstrophy (CPRE), real-time coaching, ongoing video capture and review of video footage, prospective data collection, and routine patient data analysis, with the goal of optimizing the surgical procedure to minimize devastating complications such as glans ischemia and bladder dehiscence while maximizing the rate of volitional voiding with continence and long-term protection of the upper tracts. This study reports on our short-term complications and intermediate-term continence outcomes. MATERIALS AND METHODS: A single prospective database for all patients undergoing surgery with a BE epispadias complex diagnosis at 3 institutions since February 2013 was used. For this study, data for children with a diagnosis of classic BE who underwent primary CPRE from February 2013 to February 2021 were collected. Data recorded included sex, age at CPRE, adjunct surgeries including ureteral reimplantations and hernia repairs at the time of CPRE, osteotomies, and immobilization techniques, and subsequent surgeries. Data on short-term postoperative outcomes, defined as those occurring within the first 90 days after surgery, were abstracted. In addition, intermediate-term outcomes were obtained for patients operated on between February 2013 and February 2017 to maintain a minimum follow-up of 4 years. Outcomes included upper tract dilation on renal and bladder ultrasound, presence of vesicoureteral reflux, cortical defects on nuclear scintigraphy, and continence status. Bladder emptying was assessed with respect to spontaneous voiding ability, need for clean intermittent catheterization, and duration of dry intervals. All operating room encounters that occurred subsequent to initial CPRE were recorded. RESULTS: CPRE was performed in 92 classic BE patients in the first 8 years of the collaboration (62 boys), including 46 (29 boys) during the first 4 years. In the complete cohort, the median (interquartile range) age at CPRE was 79 (50.3) days. Bilateral iliac osteotomies were performed in 89 (97%) patients (42 anterior and 47 posterior). Of those undergoing osteotomies 84 were immobilized in a spica cast (including the 3 patients who did not have an osteotomy), 6 in modified Bryant's traction, and 2 in external fixation with Buck's traction. Sixteen (17%) patients underwent bilateral ureteral reimplantations at the time of CPRE. Nineteen (21%) underwent hernia repair at the time of CPRE, 6 of which were associated with orchiopexy. Short-term complications within 90 days occurred in 31 (34%), and there were 13 subsequent surgeries within the first 90 days. Intermediate-term outcomes were available for 40 of the 46 patients, who have between 4 and 8 years of follow-up, at a median of 5.7 year old. Thirty-three patients void volitionally, with variable dry intervals. CONCLUSIONS: Cumulative efforts of prospective data collection have provided granular data for evaluation. Short-term outcomes demonstrate no devastating complications, that is, penile injury or bladder dehiscence, but there were other significant complications requiring further surgeries. Intermediate-term data show that boys in particular show encouraging spontaneous voiding and continence status post CPRE, while girls have required modification of the surgical technique over time to address concerns with urinary retention. Overall, 40% of children with at least 4 years of follow-up are voiding with dry intervals of > 1 hour.

More than the SRY: The Non-Coding Landscape of the Y Chromosome and Its Importance in Human Disease.

Historically, the Y chromosome has presented challenges to classical methodology and philosophy of understanding the differences between males and females. A genetic unsolved puzzle, the Y chromosome was the last chromosome to be fully sequenced. With the advent of the Human Genome Project came a realization that the human genome is more than just genes encoding proteins, and an entire universe of RNA was discovered. This dark matter of biology and the black box surrounding the Y chromosome have collided over the last few years, as increasing numbers of non-coding RNAs have been identified across the length of the Y chromosome, many of which have played significant roles in disease. In this review, we will uncover what is known about the connections between the Y chromosome and the non-coding RNA universe that originates from it, particularly as it relates to long non-coding RNAs, microRNAs and circular RNAs.

Targeted multispectral filter array design for the optimization of endoscopic cancer detection in the gastrointestinal tract.

Significance: Color differences between healthy and diseased tissue in the gastrointestinal (GI) tract are detected visually by clinicians during white light endoscopy; however, the earliest signs of cancer are often just a slightly different shade of pink compared to healthy tissue making it hard to detect. Improving contrast in endoscopy is important for early detection of disease in the GI tract during routine screening and surveillance. Aim: We aim to target alternative colors for imaging to improve contrast using custom multispectral filter arrays (MSFAs) that could be deployed in an endoscopic "chip-on-tip" configuration. Approach: Using an open-source toolbox, Opti-MSFA, we examined the optimal design of MSFAs for early cancer detection in the GI tract. The toolbox was first extended to use additional classification models (k-nearest neighbor, support vector machine, and spectral angle mapper). Using input spectral data from published clinical trials examining the esophagus and colon, we optimized the design of MSFAs with three to nine different bands. Results: We examined the variation of the spectral and spatial classification accuracies as a function of the number of bands. The MSFA configurations tested showed good classification accuracies when compared to the full hyperspectral data available from the clinical spectra used in these studies. Conclusion: The ability to retain good classification accuracies with a reduced number of spectral bands could enable the future deployment of multispectral imaging in an endoscopic chip-on-tip configuration using simplified MSFA hardware. Further studies using an expanded clinical dataset are needed to confirm these findings.

Observed Structured Teaching Experiences (OSTEs) in a Students as Teachers Course.

Introduction: Teaching is an important competency in graduate medical education (GME). Many residency programs have implemented curricula to develop residents' teaching skills and observed structured teaching experiences (OSTEs) have been used to assess these skills. There is an increasing focus on building teaching skills earlier in the medical education continuum, however, there is limited literature on assessing medical students' teaching skills. The authors developed an OSTE for medical students enrolled in a students-as-teachers course to address this gap and provide formative feedback on teaching skills. Materials and Methods: OSTEs were conducted for fourth-year medical students (M4s) enrolled in a Students as Teachers Advanced Elective at a US medical school. An M4 observed a first-year medical student (M1) during a simulated encounter with a standardized patient. The M4 gave feedback and a chalk talk. A physician observer assessed the M4's teaching using the modified Stanford Faculty Development Program (SFDP) questionnaire. The M1s and M4s also completed the SFDP. The M4 completed pre- and post-OSTE self-efficacy surveys (score range 6-30) and a post-OSTE acceptability survey. Results: All (30/30) M4s completed the OSTE. The SFDP identified common teaching strengths and areas for growth. ANOVA tests demonstrated significant differences between the mean (SD) scores from physician assessors, M1s, and M4s [4.56 (0.63) vs. 4.87 (0.35) vs. 4.08 (0.74), p<0.001]. There was a statistically significant difference in mean (SD) self-efficacy scores pre- and post-OSTE [18.72 (3.39) vs. 23.83 (3.26), p<0.001]. All M4s (30/30) somewhat or strongly agreed with all three OSTE acceptability questions. Lessons Learned: The authors successfully conducted an OSTE in an M4 advanced elective. The OSTE was highly acceptable to participants, and M4s demonstrated improved teaching self-efficacy. Further research should explore the validity of the OSTE to measure medical students' teaching skills and the long-term impact of developing teaching skills in medical school. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-023-01952-3.

Skeletal muscle relaxants as adjunctive pain control following cardiothoracic surgery: a systematic review protocol.

INTRODUCTION: Multimodal pain control following cardiothoracic surgery remains a focus in international guidelines. We hypothesise that non-depolarising skeletal muscle relaxants can prove to be a useful adjunct for this population. METHODS/ANALYSIS: This systematic review will focus on human adult studies of pain control using muscle relaxants within 1 week following cardiac and thoracic surgery available in PubMed, Cochrane Central, Web of Science and EMBASE. Target studies will have a primary focus on measured effects on quality of pain control and reduction in opioid usage. Studies that include non-depolarising skeletal muscle relaxants given during cardiothoracic surgery or in the week after will be included. Study selection will be in keeping with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Procedures and agents used will be analysed together, and a meta-analysis will be conducted then compared with current therapies recommended in international practice guidelines. ETHICS AND DISSEMINATION: Formal ethical approval will not be required as primary data will not be collected. The results will be disseminated through peer-reviewed publication, conference presentation and lay press. PROSPERO REGISTRATION NUMBER: CRD42023397917.

An environmental evaluation of urine-diverting dry toilets in Hiloweyn Camp, Dollo Ado, Ethiopia.

Safe and hygienic management of human waste is essential in humanitarian settings. Urine-diverting dry toilets (UDDTs) can enable this management in some humanitarian emergency settings. A seeded, longitudinal environmental study was conducted in Hiloweyn refugee camp, Dollo Ado, Ethiopia, to measure Escherichia coli and Ascaris suum ova inactivation within closed UDDT vaults and to document environmental conditions (temperature, moisture content, and pH) that could influence inactivation. Hiloweyn camp represented an optimal location for a desiccation-based sanitation technology such as the UDDT. E. coli and Ascaris ova inactivation was observed in UDDTs under warm, dry, alkaline conditions at 6, 9, and 12 months of storage; UDDTs with samples containing <1000 E. coli/g total solids increased from 30 % to 95 % over 12 months, and a >2.8-log10 reduction in Ascaris ova viability was observed after 6 months. Additional laboratory-based studies were conducted to provide insights into the field study findings and study the impact of hydrated lime on E. coli and Ascaris ova inactivation. Results suggest that adding hydrated lime to elevate pH > 12 may increase inactivation and decrease storage time. Overall, UDDTs could contribute to the safe and hygienic management of human waste in comparable warm and dry humanitarian settings.

Male epispadias repair: Outcomes at three sites prior to the establishment of a multi-institutional collaboration.

INTRODUCTION: Epispadias, which occurs on the more mild end of the Bladder Exstrophy Epispadias Complex (BEEC) spectrum, presents still with a wide range of severity in boys, from mild glanular epispadias to penopubic epispadias with severe urethral and bladder neck defects. Surgical management ranges from isolated epispadias repair to epispadias repair with bladder neck reconstruction (BNR) with or without pelvic osteotomies. OBJECTIVES: We aimed to evaluate outcomes in epispadias treated at three institutions prior to formation of a formal collaboration. In addition, we sought to delineate outcomes based on anatomic severity at time of diagnosis, and initial procedure performed in cases of penopubic epispadias. METHODS: IRB approved databases were retrospectively queried at three institutions for patients who underwent repair of epispadias between 1/1993 and 1/2013. Degree of epispadias, age and technique at initial repair, and self-reported continence status at last follow-up were recorded. Continence was categorized as: wet, intermediate (dry 2-3 h), or dry, while also distinguishing those who void and those who require clean intermittent catheterization (CIC). Those not seen since 1/1/2015, younger than 10 years at last follow up, or in whom continence data were not recorded were excluded. RESULTS: A total of 48 boys were identified; 36 met inclusion criteria. The epispadias cohort consisted of 8 glanular epispadias (GE) (22%); 8 penile epispadias (PE) (22%), and 20 penopubic epispadias (PPE) (56%) with a median follow-up of 11.3 years (3.2-26.2 years). Overall, 33 of 36 (92%) boys void per urethra. Within the group that voids, 19/33 (58%) are completely dry, while 6/33 (18%) are wet. Among patients who underwent initial epispadias repair without concurrent or subsequent bladder neck reconstruction, continence rates were: GE 63% (5/8); PE 75% (6/8); PPE 71% (5/7). Among the 9 boys with PPE who underwent initial epispadias repair with concurrent BNR, 22% (2/9) were dry with no further surgeries. Overall, 8/20 (40%) of boys with PPE void with complete dryness. DISCUSSION: This multi-center retrospective review of continence in epispadias demonstrates that even some boys with glanular and penile epispadias can have challenges with continence, and boys with penopubic epispadias may remain wet despite careful preoperative assessment of bladder neck functionality and concurrent BNR. CONCLUSION: Continence outcomes in boys with all degrees of epispadias can be variable. Even boys with more distal defects may have significant bladder neck deficiency. And those with the most severe form of epispadias may require bladder neck reconstruction to achieve continence.

Effect of heat stress on the hypothalamic expression of water channel- and noncoding RNA biogenesis-related genes in modern broilers and their ancestor red jungle fowl.

Genetic selection for high growth rate has resulted in spectacular progress in feed efficiency in chickens. As feed intake and water consumption (WC) are associated and both are affected by environmental conditions, we evaluated WC and its hypothalamic regulation in three broiler-based research lines and their ancestor jungle fowl (JF) under heat stress (HS) conditions. Slow growing ACRB, moderate growing 95RB, fast growing MRB, and JF were exposed to daily chronic cyclic HS (36 °C, 9 h/d) or thermoneutral temperature (24 °C). HS increased WC in the MRB only. Arginine vasopressin (AVP) mRNA levels were decreased by HS in the MRB. Within the renin-angiotensin-aldosterone system (RAAS) system, renin expression was increased by HS in the JF, ACRB, and 95RB, while angiotensin I-converting enzyme (ACE), angiotensin II receptors (type 1, AT1, and type 2, AT2) were affected by line. The expression of aquaporin (AQP2, 7, 9, 10, 11, and 12) genes was upregulated by HS, whereas AQP4 and AQP5 expressions were influenced by line. miRNA processing components (Dicer1, Ago2, Drosha) were significantly different among the lines, but were unaffected by HS. In summary, this is the first report showing the effect of HS on hypothalamic water channel- and noncoding RNA biogenesis-related genes in modern chicken populations and their ancestor JF. These results provide a novel framework for future research to identify new molecular mechanisms and signatures involved in water homeostasis and adaptation to HS.

Incidence of Hypertriglyceridemia in Patients on Propofol, Clevidipine, or Both.

BACKGROUND: Propofol and clevidipine (PC) are commonly used in the treatment of critically ill patients. While both medications are lipid emulsions, there is limited evidence concerning the incidence of hypertriglyceridemia (HTG) when these agents are used individually or concurrently. OBJECTIVE: The objective of this study is to determine the effects of propofol, clevidipine, or concurrent PC on triglycerides (TGs) and related outcomes in critically ill adults. METHODS: This was a retrospective cohort study conducted at an academic medical center. Patients were included if they received ≥24 hours of continuous propofol and/or clevidipine. Excluded were those without TG levels after ≥24 hours of infusion, baseline HTG, acute pancreatitis at admission, or receiving total parenteral nutrition with lipids. The primary outcome was incidence of HTG (defined as a TG level >400 mg/dL). Secondary outcomes included median and peak TG levels, hospital length of stay, intensive care unit length of stay, total lipid infused, time to peak TG level, peak lipase level, and development of pancreatitis. RESULTS: In total, 190 patients were studied: 109 in the propofol group, 50 in the clevidipine group, and 31 in the PC group. Incidence of HTG was similar (19 [17.4%] vs 6 [12%] vs 4 [12.9%] patients, P = 0.6246). Peak and median TG levels were similar for propofol, clevidipine, and PC groups (216 mg/dL vs 189.5 mg/dL vs 205 mg/dL, P = 0.7069; 177 mg/dL vs 185.5 mg/dL vs 177 mg/dL, P = 0.6791). CONCLUSIONS AND RELEVANCE: There was a similar incidence of HTG in all groups. The results of this study suggest that the concurrent use of PC should not modify the frequency of TG level monitoring.

Spatial profiling reveals tissue-specific neuro-immune interactions in gastroenteropancreatic neuroendocrine tumors.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are heterogeneous malignancies that arise from complex cellular interactions within the tissue microenvironment. Here, we sought to decipher tumor-derived signals from the surrounding microenvironment by applying digital spatial profiling (DSP) to hormone-secreting and non-functional GEP-NETs. By combining this approach with in vitro studies of human-derived organoids, we demonstrated the convergence of cell autonomous immune and pro-inflammatory proteins that suggests their role in neuroendocrine differentiation and tumorigenesis. DSP was used to evaluate the expression of 40 neural- and immune-related proteins in surgically resected duodenal and pancreatic NETs (n = 20) primarily consisting of gastrinomas (18/20). A total of 279 regions of interest were examined between tumors, adjacent normal and abnormal-appearing epithelium, and the surrounding stroma. The results were stratified by tissue type and multiple endocrine neoplasia I (MEN1) status, whereas protein expression was validated by immunohistochemistry (IHC). A tumor immune cell autonomous inflammatory signature was further evaluated by IHC and RNAscope, while functional pro-inflammatory signaling was confirmed using patient-derived duodenal organoids. Gastrin-secreting and non-functional pancreatic NETs showed a higher abundance of immune cell markers and immune infiltrate compared with duodenal gastrinomas. Compared with non-MEN1 tumors, MEN1 gastrinomas and preneoplastic lesions showed strong immune exclusion and upregulated expression of neuropathological proteins. Despite a paucity of immune cells, duodenal gastrinomas expressed the pro-inflammatory and pro-neural factor IL-17B. Treatment of human duodenal organoids with IL-17B activated NF-κB and STAT3 signaling and induced the expression of neuroendocrine markers. In conclusion, multiplexed spatial protein analysis identified tissue-specific neuro-immune signatures in GEP-NETs. Duodenal gastrinomas are characterized by an immunologically cold microenvironment that permits cellular reprogramming and neoplastic transformation of the preneoplastic epithelium. Moreover, duodenal gastrinomas cell autonomously express immune and pro-inflammatory factors, including tumor-derived IL-17B, that stimulate the neuroendocrine phenotype. © 2024 The Pathological Society of Great Britain and Ireland.

Combined flat-field and frequency filter approach to correcting artifacts of multichannel two-photon microscopy.

Significance: Multiphoton microscopy (MPM) is a useful biomedical imaging tool for its ability to probe labeled and unlabeled depth-resolved tissue biomarkers at high resolution. Automated MPM tile scanning allows for whole-slide image acquisition but can suffer from tile-stitching artifacts that prevent accurate quantitative data analysis. Aim: We have investigated postprocessing artifact correction methods using ImageJ macros and custom Python code. Quantitative and qualitative comparisons of these methods were made using whole-slide MPM autofluorescence and second-harmonic generation images of human duodenal tissue. Approach: Image quality after artifact removal is assessed by evaluating the processed image and its unprocessed counterpart using the root mean square error, structural similarity index, and image histogram measurements. Results: Consideration of both quantitative and qualitative results suggest that a combination of a custom flat-field-based correction and frequency filtering processing step provide improved artifact correction when compared with each method used independently to correct for tiling artifacts of tile-scan MPM images. Conclusions: While some image artifacts remain with these methods, further optimization of these processing steps may result in computational-efficient methods for removing these artifacts that are ubiquitous in large-scale MPM imaging. Removal of these artifacts with retention of the original image information would facilitate the use of this imaging modality in both research and clinical settings, where it is highly useful in collecting detailed morphologic and optical properties of tissue.

Nonclinical pharmacokinetics, pharmacodynamics and safety assessment of a FLT3L-Fc molecule for cancer immunotherapy.

FLT3L-Fc is a cytokine-Fc fusion agonizing receptor-type tyrosine-protein kinase FLT3 (fms-related tyrosine kinase 3; CD135). FLT3 is expressed on dendritic cells (DCs) as well as myeloid and lymphoid progenitors. Nonclinical pharmacokinetics, pharmacodynamics and safety of FLT3L-Fc were investigated in rats and cynomolgus monkeys. FLT3L-Fc induced robust pharmacodynamic responses, evidenced by marked expansion of peripheral blood cDC1s, cDC2s, and pDCs (up to 301-fold in rats and 378-fold in monkeys), peaking at 8-10 days after the first dose. FLT3L-Fc was well tolerated with no adverse findings at doses up to 10 mg/kg administered intravenously twice three weeks apart. In both species, major clinical pathology findings consisted of expansion of white blood cell (WBC) populations including lymphocytes, monocytes, neutrophils, basophils, and large unstained cells, which were pronounced after the first dose. The WBC findings were associated microscopically with histiocytic and mononuclear cell infiltrates in multiple organs. Tissue immunohistochemistry in monkeys showed that the leukocyte infiltrates consisted of hematopoietic progenitor cells and histiocytes with a reactive morphology and were associated with a slight stimulation of regional T and B cell populations. Additional FLT3L-Fc-associated changes included decreases in red blood cell (RBC) mass, increases in RBC distribution width, variable changes in reticulocytes, and transient alterations in platelet counts (rats only). The RBC and WBC findings were associated microscopically with increased hematopoietic cellularity of the bone marrow in both species and increased splenic megakaryocytic extramedullary hematopoiesis in rats. The totality of nonclinical safety data support the clinical development of FLT3L-Fc.

Identifying critical quality metrics in Mohs Surgery: A national expert consensus process.

BACKGROUND: Amid a movement toward value-based healthcare, increasing emphasis has been placed on outcomes and cost of medical services. To define and demonstrate the quality of services provided by Mohs surgeons, it is important to identify and understand the key aspects of Mohs micrographic surgery (MMS) that contribute to excellence in patient care. OBJECTIVE: The purpose of this study is to develop and identify a comprehensive list of metrics in an initial effort to define excellence in MMS. METHODS: Mohs surgeons participated in a modified Delphi process to reach a consensus on a list of metrics. Patients were administered surveys to gather patient perspectives. RESULTS: Twenty-four of the original 66 metrics met final inclusion criteria. Broad support for the initiative was obtained through physician feedback. LIMITATIONS: Limitations of this study include attrition bias across survey rounds and participation at the consensus meeting. Furthermore, the list of metrics is based on expert consensus instead of quality evidence-based outcomes. CONCLUSION: With the goal of identifying metrics that demonstrate excellence in performance of MMS, this initial effort has shown that Mohs surgeons and patients have unique perspectives and can be engaged in a data-driven approach to help define excellence in the field of MMS.

Evaluating backscattering polarized light imaging microstructural mapping capabilities through neural tissue and analogous phantom imaging.

Significance: Knowledge of fiber microstructure and orientation in the brain is critical for many applications. Polarized light imaging (PLI) has been shown to have potential for better understanding neural fiber microstructure and directionality due to the anisotropy in myelin sheaths surrounding nerve fibers of the brain. Continuing to advance backscattering based PLI systems could provide a valuable avenue for in vivo neural imaging. Aim: To assess the potential of backscattering PLI systems, the ability to resolve crossing fibers, and the sensitivity to fiber inclination and curvature are considered across different imaging wavelengths. Approach: Investigation of these areas of relative uncertainty is undergone through imaging potential phantoms alongside analogous regions of interest in fixed ferret brain samples with a five-wavelength backscattering Mueller matrix polarimeter. Results: Promising phantoms are discovered for which the retardance, diattenuation and depolarization mappings are derived from the Mueller matrix and studied to assess the sensitivity of this polarimeter configuration to fiber orientations and tissue structures. Conclusions: Rich avenues for future study include further classifying this polarimeter's sensitivity to fiber inclination and fiber direction to accurately produce microstructural maps of neural tissue.