Self-assembling peptide hydrogel SPG-178 as a pancreatic fistula-preventing agent.

PURPOSE: Pancreatic fistula (PF) is a common and challenging complication after pancreatic surgery. The aim of this study was to investigate the efficacy of a new method for preventing PF utilizing self-assembling peptide hydrogel SPG-178 as a preclinical study. METHODS: The degradability of SPG-178 was confirmed by mixing it with protease. A PF rat model was then established to investigate the efficacy of SPG-178 at preventing PF. After transecting the pancreatic duct toward the spleen, SPG-178 was attached to both sides of the pancreatic stump. The levels of amylase and lipase in both the serum and ascites were measured and surgical specimens investigated pathologically. RESULTS: The hardness of SPG-178 did not change when treated with protease over a short period. The ascitic amylase level was significantly lower in rats treated with SPG-178 than rats who were not 3 days after transection of the pancreatic duct toward the spleen. Pathological examination showed fewer inflammatory cells and presence of a structure body on the surface of the pancreatic stump in the SPG-178-treated group. SPG-178 remained on the surface and many cells that covered it formed fibrous tissue or mesothelium. CONCLUSION: Self-assembling peptide hydrogel SPG-178 has potential as a tool for preventing PF.

Guidance on the need for contraception related to use of pharmaceuticals: the Japan Agency for Medical Research and Development Study Group for providing information on the proper use of pharmaceuticals in patients with reproductive potential.

BACKGROUND: The U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) have published guidelines on the use of cancer treatments in young people of reproductive potential. However, no such guideline is available in Japan. Therefore, this project aimed to gather relevant data and draft a respective guidance paper. METHODS: From April 2019 to March 2021, the Study Group for Providing Information on the Proper Use of Pharmaceuticals in Patients with Reproductive Potential at the Japan Agency for Medical Research and Development gathered opinions from experts in reproductive medicine, toxicology, and drug safety measures. The group considered these opinions, the FDA and EMA guidelines, and relevant Japanese guidelines and prepared a guidance paper, which they sent to 19 related organizations for comment. RESULTS: By November 2020, the draft guidance paper was completed and sent to the related organizations, 17 of which provided a total of 156 comments. The study group finalized the guidance paper in March 2021. CONCLUSIONS: The "Guidance on the Need for Contraception Related to Use of Pharmaceuticals" (The report of the Study Group for Providing Information on the Proper Use of Pharmaceuticals in Patients with Reproductive Potential, Research on Regulatory Science of Pharmaceuticals and Medical Devices, Japan Agency for Medical Research and Development: JP20mk0101139) is expected to help Japanese healthcare professionals provide fertility-related care and advice to adolescents, and young adults with cancer and their families.

Corneal Opacity Induced by Light in a Mouse Model of Gelatinous Drop-Like Corneal Dystrophy.

Gelatinous drop-like corneal dystrophy (GDLD) is a severe inherited corneal dystrophy characterized by subepithelial corneal amyloid deposition. We had previously succeeded in identifying the responsible gene, TACSTD2, and subsequently found that the epithelial barrier function is significantly decreased. As with GDLD patients, the knockout mice showed severe loss of tight junction, progressive opacity, and neovascularization in the cornea. We devised an easy method to confirm the loss of the corneal barrier function even before corneal opacity is observed. Furthermore, by using knockout mice, we were able to verify clinical findings, such as the wound healing delay and light-induced acceleration of the disease. This mouse model should prove to be a highly useful tool for investigating the pathology of GDLD and for developing new therapies.

Synthesis and anti-human immunodeficiency virus activity of the skeleton isomers of 3',4'-Di-(O)-(-)-camphanoyl-(+)-khellactone.

Optically active structural isomers (1b-f and dst-1b-f) of 3',4'-di-(O)-(-)-camphanoyl-(+)-khellactone (DCK) were synthesized and their anti-human immunodeficiency virus (HIV) activity was investigated. The value of the sensitivity index (SI) of 1b was greater than that of DCK.

Assessment of a self-assembling peptide gel, SPG-178, in providing a clear operative field for trabeculectomy surgery for glaucoma in an animal model.

The presence of blood during ophthalmic surgery is problematic, as it can obstruct a surgeon's view of the operative field. This is particularly true when performing trabeculectomy surgery to enhance ocular fluid outflow and reduce intraocular pressure as a treatment for glaucoma, one of the most common vision loss conditions worldwide. In this study, we investigated the performance of a transparent, self-assembling peptide gel (SPG-178) and its ability to maintain visibility during trabeculectomy surgery. Unlike the hyaluronic acid gel commonly used in ophthalmic surgery, SPG-178 did not permit the ingress of blood into the gel itself. Rather, it forced blood to flow peripherally to the gel. Moreover, if bleeding occurred under the SPG-178 gel, perfusion with saline was able to effectively flush the blood away along the interface between the SPG-178 and the ocular tissue (in this case scleral) to clear the surgical field of view. In experimental trabeculectomy surgeries with mitomycin C used as an adjuvant, there were no differences in the postoperative recovery of intraocular pressure or bleb morphology with or without the use of SPG-178. SPG-178, therefore, when used in a gel formulation, represents a new material for use in intraocular surgery to ensure a clear operative field with likely beneficial treatment outcomes.

A Self-Assembling Peptide Gel as a Vitreous Substitute: A Rabbit Study.

Purpose: To evaluate a self-assembling peptide gel as a potential vitreous substitute. Methods: PanaceaGel SPG-178, a self-assembling peptide gel, was diluted with distilled water and a balanced salt solution to achieve a final peptide concentration of 0.1%. The gel's refractive index, visible light transmission rate, and rheologic properties were investigated. The gel's biocompatibility was evaluated by examining the cellular viability (live and dead staining) and proliferation rate (alamarBlue assay). A 25-G pars plana vitrectomy was performed on the right eye of 21 New Zealand white rabbits. The gel was then injected into the vitreous cavity of 15 eyes. Six eyes were injected with a balanced salt solution (BSS) and served as controls. Toxicity was examined using electroretinography and histologic analysis after the injection of the gel. Results: The gel's physical properties closely resembled those of human vitreous. The gel showed no apparent toxicity. When the gel was injected into the vitreous cavity, fragmentation was not observed. Additionally, the gel remained transparent in the vitreous cavity and no complications were observed for 3 months after the injection. Electroretinography and histology confirmed the gel's biocompatibility. Conclusions: This diluted self-assembling peptide gel could be provide a promising vitreous substitute.