An FDA-Validated, Self-Cleaning Liquid Chromatography-Mass Spectrometry System for Determining Small-Molecule Drugs and Metabolites in Organoid/Organ-on-Chip Medium.

As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography-mass spectrometry (LC-MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC-MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.

Addressing corneal opacity after herpes zoster infection.

A 15-year-old boy was referred for corneal opacity evaluation. The patient had a previous herpes zoster virus (HZV) infection-varicella-zoster virus (VZV)-with ocular manifestation 1 year ago. After the infection, he developed a central corneal scar and decreased corrected distance visual acuity (CDVA) in the right eye. The slitlamp examination showed the right eye with central corneal opacity (involving anterior stroma), lacuna area between the haze, fluorescein negative, and no vascularization near the scar (Figure 1JOURNAL/jcrs/04.03/02158034-202406000-00019/figure1/v/2024-07-10T174224Z/r/image-tiff). The patient had been treated with oral valacyclovir and topical corticosteroids without any improvement of visual acuity or changes in opacity within the 1-year follow-up. His CDVA was 20/200 (-4.50 -0.75 × 25) in the right eye and counting fingers (-4.00) in the left eye. Intraocular pressure was 12 mm Hg in both eyes. Fundoscopy was normal in the right eye, but he had a macular scar in the left eye (diagnosed when he was 7 years). The left eye had no cornea signs. The patient has no comorbidity or previous surgeries. Considering this case, a corneal central scar in a 15-year-old boy, legally single eye only, and assuming it is an opacity in the anterior stroma, would you consider surgery for this patient? If so, which would you choose: Would you consider an excimer laser treatment of his ametropia while partially removing his opacity, a phototherapeutic keratectomy (PTK), or a PTK followed by a topography-guided treatment, femtosecond laser-assisted anterior lamellar keratoplasty (FALK), or deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (depending on the scar depth)? Would you consider prophylactic acyclovir during and after surgery? Would you consider any other surgical step to prevent delayed corneal healing-persistent epithelial defect? Before the surgical approach, would you consider treating this patient with topical losartan (a transforming growth factor [TGF]-ß signaling inhibitor)? Would you first perform the surgery (which one) and then start the medication? Furthermore, if so, how long would you treat this patient? Would you consider treatment with another medication?

In vitro gastrointestinal stability and intestinal absorption of ACE-1 and DPP4 inhibitory peptides from poultry by-product hydrolysates.

Bioactive peptides derived from food are promising health-promoting ingredients that can be used in functional foods and nutraceutical formulations. In addition to the potency towards the selected therapeutic target, the bioavailability of bioactive peptides is a major factor regarding clinical efficacy. We have previously shown that a low molecular weight peptide fraction (LMWPF) from poultry by-product hydrolysates possesses angiotensin-1-converting enzyme (ACE-1) and dipeptidyl-peptidase 4 (DPP4) inhibitory activities. The present study aimed to investigate the bioavailability of the bioactive peptides in the LMWPF. Prior to the investigation of bioavailability, a dipeptide YA was identified from this fraction as a dual inhibitor of ACE-1 and DPP4. Gastrointestinal (GI) stability and intestinal absorption of the bioactive peptides (i.e., YA as well as two previously reported bioactive dipeptides (VL and IY)) in the LMWPF were evaluated using the INFOGEST static in vitro digestion model and intestinal Caco-2 cell monolayer, respectively. Analysis of peptides after in vitro digestion confirmed that the dipeptides were resistant to the simulated GI conditions. After 4 hours of incubation, the concentration of the peptide from the apical side of the Caco-2 cell monolayer showed a significant decrease. However, the corresponding absorbed peptides were not detected on the basolateral side, suggesting that the peptides were not transported across the intestinal monolayer but rather taken up or metabolized by the Caco2 cells. Furthermore, when analyzing the gene expression of the Caco-2 cells upon peptide stimulation, a down-regulation of peptide transporters, the transcription factor CDX2, and the tight junction protein-1 (TJP1) was observed, suggesting the specific effects of the peptides on the Caco-2 cells. The study demonstrated that bioactive dipeptides found in the LMWPF were stable through in vitro GI digestion; however, the overall bioavailability may be hindered by inadequate uptake across the intestinal barrier.

Short-term revision rate of Rigicon Testi10TM testicular prosthesis in adolescents and adults: a retrospective chart review.

Testicular prosthesis implantation is a valuable solution for the physical, cosmetic, and psychological challenges associated with testicular loss which may affect males of any age. We evaluated the safety and reliability of the new Rigicon Testi10TM testicular prosthesis in adults and adolescents by performing an IRB-approved retrospective study of data drawn from Patient Information Forms (PIFs). A total of 427 patients (382 adults and 45 adolescents) had at least one testicular prosthesis implanted. Only one adult patient required revision surgery due to rupture of the Rigicon Testi10 TM saline-filled prosthesis. A 40-year-old patient was found to have a leaking prosthesis approximately one week postoperatively, which was suspected to be due to inadvertently punctured by the surgeon during the sterile saline filling process. There were no post-implantation revisions required for adolescent patients. According to our results, Kaplan-Meier calculation of survival from removal or revision was 99.8% for all patients at 54 months (99.7% for adults and 100% for adolescents). The complication rates among patients in this study are lower than those reported in previous published studies. Our study underscores the generally safe nature of testicular prosthesis implantation, as well as the very rare incidence of revision surgery for this new device.

Salzmann's Nodular Degeneration in Refractive Surgery: The Earlier Hit Hypothesis of EBM Injury-Related Fibrosis of the Subepithelial Space and Deeper Corneal Extension.

PURPOSE: To review the atypical development of Salzmann's nodular degeneration (SND) after two cases of laser in situ keratomileusis (LASIK) and one case of photorefractive keratomileusis (PRK), and to highlight the pathophysiology of SND and its treatment. METHODS: Three cases of SND (two following LASIK performed with microkeratomes and one following PRK) were reviewed and Pubmed.gov and internet searches were performed. RESULTS: SND is myofibroblast-generated fibrosis in the subepithelial space between the epithelium and Bowman's layer that develops years or decades after traumatic, surgical, infectious, or inflammatory injuries to the cornea in which the epithelial basement membrane is damaged in one or more locations and does not fully regenerate. It is hypothesized based on these cases, and the previous immunohistochemistry of other investigators, that myofibroblast precursors, such as fibrocytes or corneal fibroblasts, that enter the subepithelial space are driven to develop into myofibroblasts, which slowly proliferate and extend the fibrosis, by transforming growth factor-beta from epithelium and tears that passes through the defective epithelial basement membrane. These myofibroblasts and the disordered collagens, and other extracellular matrix components they produce, make up the subepithelial opacity characteristic of SND. Nodules are larger accumulations of myofibroblasts and disordered extracellular matrix. If the injury is associated with damage to the underlying Bowman's layer and stroma, as in LASIK flap generation, then the myofibroblasts and fibrosis can extend into Bowman's layer and the underlying anterior stroma. CONCLUSIONS: SND fibrosis often extends into Bowman's layer and the anterior stroma if there are associated Bowman's defects, such as incisions or lacerations. In the latter cases, SND frequently cannot be removed by simple scrape and peel, as typically performed for most common SND cases, but can be trimmed to remove the offending tissue. This condition is more accurately termed Salzmann's subepithelial fibrosis. [J Refract Surg. 2024;40(5):e279-e290.].

Measuring resilience for Chinese-speaking populations: a systematic review of Chinese resilience scales.

Introduction: Despite the rapid growth of interdisciplinary resilience research in Chinese contexts, no study has systematically reviewed individual-level measurement scales for Chinese-speaking populations. We report a systematic review of scales developed for or translated/adapted to Chinese-speaking contexts, where we assessed how widely used scales fare in terms of their psychometric qualities. Methods: Studies included in this review must have been published in peer-reviewed English or Chinese journals between 2015-2020 and included self-reported resilience scales in Chinese-speaking populations. Searches were conducted in PsycINFO, CNKI (completed in May 2021), and PubMed (completed in January 2024). We developed coding schemes for extracting relevant data and adapted and applied an existing evaluation framework to assess the most frequently used resilience scales by seven methodological criteria. Results: Analyses of 963 qualified studies suggested that Chinese resilience scales were used in a diverse range of study contexts. Among 85 unique kinds of resilience measures, we highlighted and evaluated the three most frequently used translated scales and three locally developed scales (nine scales in total including variations such as short forms). In short, resilience studies in Chinese contexts relied heavily on the translated 25-item Connor-Davidson Resilience Scale, which scored moderately on the overall quality. The locally developed Resilience Scale for Chinese Adolescents and Essential Resilience Scale received the best ratings but could use further development. Discussion: We discussed how future work may advance widely used scales, and specified seven methodological recommendations for future resilience scale development with existing and new scales in and beyond the Chinese study contexts. We further addressed issues and challenges in measuring resilience as a process and called on researchers to further develop/evaluate process measures for Chinese-speaking populations.

Two-phase mechanism in the treatment of corneal stromal fibrosis with topical losartan.

Recent studies in rabbits and case reports in humans have demonstrated the efficacy of topical losartan in the treatment of corneal scarring fibrosis after a wide range of injuries, including chemical burns, infections, surgical complications, and some diseases. It is hypothesized that the effect of losartan on the fibrotic corneal stroma occurs through a two-phase process in which losartan first triggers the elimination of myofibroblasts by directing their apoptosis via inhibition of extracellular signal-regulated kinase (ERK)-mediated signal transduction, and possibly through signaling effects on the viability and development of corneal fibroblast and fibrocyte myofibroblast precursor cells. This first step likely occurs within a week or two in most corneas with fibrosis treated with topical losartan, but the medication must be continued for much longer until the epithelial basement membrane (EBM) is fully regenerated or new myofibroblasts will develop from precursor cells. Once the myofibroblasts are eliminated from the fibrotic stroma, corneal fibroblasts can migrate into the fibrotic tissue and reabsorb/reorganize the disordered extracellular matrix (ECM) previously produced by the myofibroblasts. This second stage is longer and more variable in different eyes of rabbits and humans, and accounts for most of the variability in the time it takes for the stromal opacity to be markedly reduced by topical losartan treatment. Eventually, keratocytes reemerge in the previously fibrotic stromal tissue to fine-tune the collagens and other ECM components and maintain the normal structure of the corneal stroma. The efficacy of losartan in the prevention and treatment of corneal fibrosis suggests that it acts as a surrogate for the EBM, by suppressing TGF beta-directed scarring of the wounded corneal stroma, until control over TGF beta action is re-established by a healed EBM, while also supporting regeneration of the EBM by allowing corneal fibroblasts to occupy the subepithelial stroma in the place of myofibroblasts.

Structure of the interleukin-5 receptor complex exemplifies the organizing principle of common beta cytokine signaling.

Cytokines regulate immune responses by binding to cell surface receptors, including the common subunit beta (ßc), which mediates signaling for GM-CSF, IL-3, and IL-5. Despite known roles in inflammation, the structural basis of IL-5 receptor activation remains unclear. We present the cryo-EM structure of the human IL-5 ternary receptor complex, revealing architectural principles for IL-5, GM-CSF, and IL-3. In mammalian cell culture, single-molecule imaging confirms hexameric IL-5 complex formation on cell surfaces. Engineered chimeric receptors show that IL-5 signaling, as well as IL-3 and GM-CSF, can occur through receptor heterodimerization, obviating the need for higher-order assemblies of ßc dimers. These findings provide insights into IL-5 and ßc receptor family signaling mechanisms, aiding in the development of therapies for diseases involving deranged ßc signaling.

Himplant® subcutaneous penile implant improves penile appearance and erectile dysfunction after radical prostatectomy: a case series.

Erectile dysfunction is a major postoperative complication following radical prostatectomy. Various treatments for post- radical prostatectomy erectile dysfunction including nonsurgical phosphodiesterase-5 inhibitors, intraurethral alprostadil, intracavernosal injections and penile implant prosthesis, often yield suboptimal results. In this prospective single-center case series, we examine the efficacy and outcomes of Himplant®, a subcutaneous silicone penile implant, placement in four patients with post-radical prostatectomy erectile dysfunction who experienced limited benefits with phosphodiesterase-5 inhibitors. Patient data including demographics, prostate cancer diagnoses, erectile dysfunction characteristics, previous treatments, and outcomes were collected. Himplant® placement was performed in a standardized manner through a high scrotal incision in all cases. Follow-up evaluations were conducted to assess the effectiveness of the procedure and any associated complications. Patients were contacted and asked 15 questions regarding satisfaction and erectile function with the responses recorded. This study presents findings of high patient satisfaction, increases in flaccid penile length and girth, no incidence of adverse events, and improved erectile function following Himplant® placement post-radical prostatectomy. Accordingly, we suggest Himplant® placement in patients who are frustrated by their penile appearance and suffering from erectile dysfunction after radical prostatectomy. Further multicenter studies are warranted to validate these findings and assess long-term outcomes and patient-reported satisfaction.

Use of Himplant® for correction of residual deformity following prior treatment of peyronie's disease: a case series.

Over the years, numerous non-surgical and surgical treatment options have been explored for Peyronie's disease. Current options may result in incomplete correction of the deformity, which can be bothersome to the patient. This is a two-center case series of three patients who had previously undergone treatment for Peyronie's disease. Patient 1 underwent plication with extratunical grafting. Patient 2 underwent a series of Xiaflex® injections and then subsequent surgical plication for residual curvature. Patient 3 underwent a series of Xiaflex® injections. The Himplant® subcutaneous silicone penile prosthesis was placed in a standardized manner through a scrotal incision in all cases to mask residual penile deformities and enhance penile girth after Peyronie's disease treatment. Patients were contacted and asked 18 questions regarding satisfaction and erectile function with the responses recorded. This pilot study presents findings of high patient satisfaction, increases in flaccid penile length and girth, and an acceptable profile of adverse events following Himplant® placement. Based on our limited experience, we would consider offering Himplant® implantation when residual curvature is <40° and the penile indentation does not cause instability/buckling during penetrative sexual activity. Further research and larger studies are warranted to validate these findings and assess long-term outcomes and patient-reported satisfaction.

Prevention and Treatment of Persistent Epithelial Defects After Common Refractive Surgery Procedures.

PURPOSE: To discuss the prevention and treatment of persistent epithelial defects after the most common refractive surgeries-photorefractive keratectomy, laser in situ keratomileusis, or small incision lenticule extraction. METHODS: PubMed was used to search the medical literature. RESULTS: Persistent epithelial defects are infrequent after photorefractive keratectomy, laser in situ keratomileusis, or small incision lenticule extraction. In the authors' opinion, any persistent epithelial defect present at 1 week or beyond after surgery should be treated aggressively with a properly fit bandage contact lens, lubrication with non-preserved artificial tears, and treatment of any eyelid abnormalities, including nocturnal lagophthalmos. Consideration should be given for presumptive treatment for herpes simplex virus or varicella zoster virus infection. If the persistent epithelial defect does not close within 2 weeks, then other measures should be considered, such as autologous serum drops, topical losartan, amniotic membranes, and topical human recombinant nerve growth factor to limit corneal scarring fibrosis and microbial infection. CONCLUSIONS: Persistent epithelial defects are among the most feared complications of refractive surgery. Timely and aggressive treatment should be instituted to close the epithelium prior to the development of scarring fibrosis and/or microbial corneal infection. [J Refract Surg. 2024;40(2):e117-e124.].

Preparative agarose gel electrophoresis for reducing matrix interferences of organoid cell medium prior to LC-MS analysis of insulin.

Organoids are 3D cell cultures with microanatomies mimicking aspects of real organs, useful for e.g. animal-free studies of development, disease, and drug discovery. The cell medium of organoid models of Langerhans islets, regulating blood glucose levels by insulin secretion, can be analyzed by liquid chromatography-mass spectrometry (LC-MS). However, organoid medium complexity is a major challenge, as matrix interferences can reduce sensitivity and selectivity, even with optimized LC-MS conditions. By applying preparative agarose gel electrophoresis-electrodialysis (PGE-ED), we were able to decrease the cell medium background signal, allowing for reduced interferences affecting LC-MS analysis of human insulin.

Topical Losartan Inhibition of Myofibroblast Generation in Rabbit Corneas With Acute Incisions.

PURPOSE: The purpose of this study was to study whether deep central corneal incisions close during topical losartan treatment and the effect of topical losartan on myofibroblast generation after incisions in rabbit corneas. METHODS: Rabbits (12) had a 0.35-mm deep radial incision from the center of the cornea into the limbus in 1 eye that was approximated with a single 10-0 nylon suture 1 mm inside the limbus. The incision was treated with 50 µL of topical 0.8 mg/mL losartan or 50 µL of balanced salt solution vehicle 6 times per day for 1 month. Standardized slitlamp photographs of the central incisions were analyzed for opacity with ImageJ before euthanasia. Triplex IHC was performed on cryofixed corneas for myofibroblast marker alpha-smooth muscle actin, mesenchymal cell marker vimentin, and basement membrane marker laminin alpha-5. Stromal α-SMA-positive myofibroblasts surrounding the incisions were quantitated with ImageJ. RESULTS: Topical losartan compared with vehicle did not affect closure of the radial incisions or the opacity that developed surrounding the incisions at 1 month after injury. Topical losartan compared with vehicle did significantly decrease the average density of stromal myofibroblasts surrounding the incisions. CONCLUSIONS: Topical losartan, a known inhibitor of transforming growth factor beta signaling, did not affect closure of deep corneal incisions. Losartan decreased myofibroblast generation surrounding nearly full-thickness radial corneal incisions compared with vehicle. The opacity at the incisions was not significantly affected by losartan-likely because corneal fibroblasts that develop in the stroma adjacent to the incisions were not changed by the losartan compared with the vehicle.

Corneal stromal localization of TGF beta isoforms in spontaneous persistent epithelial defects after PRK in rabbits.

The purpose of this study was to evaluate transforming growth factor beta (TGFß) isoform localization in rabbit corneas with spontaneous persistent epithelial defects (PEDs) after photorefractive keratectomy (PRK). Four cryofixed corneas from a previously reported series of PEDs in rabbits that had PRK were evaluated with triplex immunohistochemistry (IHC) for TGFß3, myofibroblast marker alpha-smooth muscle actin (α-SMA) and mesenchymal marker vimentin. One cornea had sufficient remaining tissue for triplex IHC for TGFß1, TGFß2, or TGFß3 (each with α-SMA and vimentin) using isoform-specific antibodies. All three TGFß isoforms were detected in the subepithelial stroma at and surrounding the PED. Some of each TGFß isoform co-localized with α-SMA of myofibroblasts, which could be TGFß isoform autocrine production by myofibroblasts or TGFß-1, -2, and -3 binding to these myofibroblasts.

Effect of Cage Change Frequency on Perinatal Mortality in C57BL/6J Mice.

Perinatal mortality is a common problem in mouse breeding colonies. Few studies have examined the influence of environmental changes on mouse pup survival. In this study, monogamous breeding cages of C57BL/6J mice were set up and randomized into 3 cage change groups: 1) cage change at 8 d after parturition, 2) cage change at 3 d after parturition, or 3) cage change at 3 d after parturition with the addition of a polycarbonate hut in the cage. Pairs were bred to produce a minimum of 4 litters. Pup survival to weaning relative to experimental cage change date, and survival rates after cage change were evaluated. The results revealed no significant differences between experimental groups. The majority of pup loss occurred within the first 24 h after birth for those pups that were alive at birth. Overall, the postpartum day of cage change did not affect the perinatal survival of mouse pups.

Developing Measures for and Testing the Theory of Communicative Disenfranchisement (TCD) in the Context of Chronic Pain.

The post-positivist articulation of the theory of communicative disenfranchisement (TCD) asserts that people subjected to disenfranchising talk (DT; talk that discredits, silences, and stereotypes) experience proximal consequences (PCs; reduced agency, perceived credibility, and ability to exercise rights and privileges) and make negative inferences about others' future interactional goals (negative goal inferences [NGIs]). Through the mediators of PCs and NGIs, DT is theorized to lead to more distal health and well-being outcomes. This article developed measures of DT, PCs, and NGIs to test the TCD's post-positivist model in the context of chronic pain. Items were developed and refined in a pilot study. Then, in two validation studies, exploratory and confirmatory factor analyses were conducted and health and well-being outcomes were assessed. Findings offer initial empirical support for the reliability and convergent, divergent, and predictive validity of the DT, PCs, and NGIs measures, as well as the model proposed in the post-positivist articulation of the TCD.