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INTRODUCTION: Amniotic membrane (AM) is a popular treatment for external ocular diseases. First intraocular implantations in other diseases reported promising results. Here, we review three cases of intravitreal epiretinal human AM (iehAM) transplantation as an adjunct treatment for complicated retinal detachment and analyze clinical safety. Possible cellular rejection reactions against the explanted iehAM were evaluated and its influence was assessed on three retinal cell lines in vitro. METHODS: Three patients with complicated retinal detachment and implanted iehAM during pars plana vitrectomy are retrospectively presented. After removal of the iehAM at subsequent surgery, tissue-specific cellular responses were studied by light microscopy and immunohistochemical staining. We investigated the influence of AM in vitro on retinal pigment epithelial cells (ARPE-19), Müller cells (Mio-M1), and differentiated retinal neuroblasts (661W) . An anti-histone DNA ELISA for cell apoptosis, a BrdU ELISA for cell proliferation, a WST-1 assay for cell viability, and a live/dead assay for cell death were performed. RESULTS: Despite the severity of the retinal detachment, stable clinical outcomes were obtained in all three cases. Immunostaining of the explanted iehAM showed no evidence of cellular immunological rejection. In vitro, there was no statistical significant change in cell death or cell viability nor were proliferative effects detected on ARPE-19, Müller cells, and retinal neuroblasts exposed to AM. CONCLUSION: iehAM was a viable adjuvant with many potential benefits for treatment of complicated retinal detachment. Our investigations could not detect any signs of rejection reactions or toxicity. Further studies are needed to evaluate this potential in more detail.
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The first microfluidic microphysiological systems (MPS) entered the academic scene more than 15 years ago and were considered an enabling technology to human (patho)biology in vitro and, therefore, provide alternative approaches to laboratory animals in pharmaceutical drug development and academic research. Nowadays, the field generates more than a thousand scientific publications per year. Despite the MPS hype in academia and by platform providers, which says this technology is about to reshape the entire in vitro culture landscape in basic and applied research, MPS approaches have neither been widely adopted by the pharmaceutical industry yet nor reached regulated drug authorization processes at all. Here, 46 leading experts from all stakeholders - academia, MPS supplier industry, pharmaceutical and consumer products industries, and leading regulatory agencies - worldwide have analyzed existing challenges and hurdles along the MPS-based assay life cycle in a second workshop of this kind in June 2019. They identified that the level of qualification of MPS-based assays for a given context of use and a communication gap between stakeholders are the major challenges for industrial adoption by end-users. Finally, a regulatory acceptance dilemma exists against that background. This t4 report elaborates on these findings in detail and summarizes solutions how to overcome the roadblocks. It provides recommendations and a roadmap towards regulatory accepted MPS-based models and assays for patients' benefit and further laboratory animal reduction in drug development. Finally, experts highlighted the potential of MPS-based human disease models to feedback into laboratory animal replacement in basic life science research.
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Alternativas aos Testes com Animais , Bem-Estar do Animal , Desenvolvimento de Medicamentos , Avaliação Pré-Clínica de Medicamentos/métodos , Dispositivos Lab-On-A-Chip , Animais , Indústria Farmacêutica , Humanos , Modelos BiológicosRESUMO
PURPOSE: To assess treatment effects following intravitreal injection of ocriplasmin for vitreomacular traction (VMT), with or without full-thickness macular hole (FTMH), in real-life setting. METHODS: This is a monocentric, retrospective, consecutive series of 82 eyes from 82 patients who underwent ocriplasmin treatment between July 2013 and December 2016. We included 57 eyes with pure VMT, 17 eyes with small FTMHs, and eight eyes with medium FTMHs. Primary outcome measures were VMT release and MH closure rates. Secondary outcomes were visual acuity (VA), morphological changes, and subjective visual impairment after 1, 3, and 6 months and at last follow-up. RESULTS: After a median follow-up of 10 months, VMT release was achieved by pharmacologic vitreolysis in 57% of all eyes, whereas the macular hole closure rate was 32%. In those presenting with five or more positive prognostic factors (PPF), eyes with pure VMT showed nonsurgical traction release in 88%, and FTMHs were released in 93%, with a closure rate of 20%. Small FTMHs closed in 41% and medium FTMHs in 13%. The mean change in VA (LogMAR) was -0.07 ± 0.24 (median - 0.10) in all eyes. Subretinal fluid accumulation and ellipsoid zone changes were seen in 31% and 37% of all eyes, respectively. They were more frequent in eyes with traction release, but were self-limited. CONCLUSIONS: In a real-life setting, release of VMT by ocriplasmin injection can be achieved in the majority of eyes, relying on a strict patient selection. Closure of FTMHs rather correlates with hole diameter than with presence of PPF, and remains a rare finding in medium FTMHs.
Assuntos
Fibrinolisina/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Perfurações Retinianas/terapia , Descolamento do Vítreo/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Intravítreas , Masculino , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/etiologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual , Vitrectomia/métodos , Descolamento do Vítreo/complicações , Descolamento do Vítreo/cirurgiaRESUMO
The aim of this study was to determine the relative safety of 4 antiviral drugs (telbivudine, tenofovir, adefovir, and entecavir) against hepatitis B virus with respect to kidney function and toxicity in male Sprague Dawley rats. The antiviral drugs were administered once daily for 4 weeks by oral gavage at â¼10 and 25-40 times the human equivalent dose. Main assessments included markers of renal toxicity in urine, magnetic resonance imaging (MRI) of kidney function, histopathology, and electron microscopic examination. Administration of adefovir at 11 and 28 mg/kg for 4 weeks caused functional and morphological kidney alterations in a time- and dose-dependent manner, affecting mainly the proximal tubules and suggesting a mechanism of toxicity related to mitochondrial degeneration/depletion. Of note, the observed adefovir-induced reduction of kidney function was not detected by the standard method of glomerular filtration rate (GFR) measurements (clearance rate of the endogenous marker, creatinine), thereby emphasizing the superiority of MRI in terms of sensitive detection of GFR in rats. For the low dose of 300 mg/kg of tenofovir, minor kidney effects such as nuclear enlargement in the tubular epithelium, and hyaline droplets accumulation were detected, which was also observed for the low dose (11 mg/kg) of adefovir. No assessments could be done at the higher dose of 600/1000 mg/kg tenofovir due to gastrointestinal tract toxicity which prevented treatment of the animals for longer than 1 week. Entecavir at 1 and 3 mg/kg and telbivudine at 600 and 1600 mg/kg caused no toxicologically relevant effects on the kidney.