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Swedish efforts to retain farmlands are part of a more comprehensive policy to enhance the economic viability of the family farm. Aside from the containment of urbanization, which is accomplished by a number of planning tools, farm rationalization is the major element in Swedish policy. Rationalization, which has generally meant the creation of larger individual farms, has allowed the family farm to achieve certain scales of economy and take advantage of technological innovations. The key actor in the rationalization and containment process has been the country agricultural board, a creature of local government with unique and comprehensive powers to regulate land markets, extend credit, provide technical advice to farmers, and organize and manage farm amalgamation. [ABSTRACT FROM PUBLISHER]

Genome editing by CRISPR-Cas holds promise for the treatment of retinal dystrophies. For therapeutic gene editing, transient delivery of CRISPR-Cas9 is preferable to viral delivery which leads to long-term expression with potential adverse consequences. Cas9 protein and its guide RNA, delivered as ribonucleoprotein (RNP) complexes, have been successfully delivered into the retinal pigment epithelium in vivo . However, the delivery into photoreceptors, the primary focus in retinal dystrophies, has not been achieved. Here, we investigate the feasibility of direct RNP delivery into photoreceptors and retinal pigment epithelium cells. We demonstrate that Cas9 or adenine-base editors complexed with guide RNA, can enter retinal cells without the addition of any carrier compounds. Once in the retinal cells, editing rates vary based on the efficacy of the guide RNA and the specific location edited within the genes. Cas9 RNP delivery at high concentrations, however, leads to outer retinal toxicity. This underscores the importance of improving delivery efficiency for potential therapeutic applications in the future., Competing Interests: D.D. is a co-inventor on patent #9193956 (Adeno-associated virus virions with variant capsid and methods of use thereof), with royalties paid to Adverum Biotechnologies and on pending patent applications on noninvasive methods to target cone photoreceptors (EP17306429.6 and EP17306430.4) licensed to Gamut Tx now SparingVision. D.D. also has personal financial interests in Tenpoint Tx. and SparingVision, outside the scope of the submitted work., (© 2024 The Author(s).)

Background: Patient engagement is the active collaboration between patient partners and health system partners towards a goal of making decisions that centre patient needs-thus improving experiences of care, and overall effectiveness of health services in alignment with the Quintuple Aim. An important but challenging aspect of patient engagement is including diverse perspectives particularly those experiencing health inequities. When such populations are excluded from decision-making in health policy, practice and research, we risk creating a healthcare ecosystem that reinforces structural marginalisation and perpetuates health inequities., Approach: Despite the growing body of literature on knowledge coproduction, few have addressed the role of power relations in patient engagement and offered actionable steps for engaging diverse patients in an inclusive way with a goal of improving health equity. To fill this knowledge gap, we draw on theoretical concepts of power, our own experience codesigning a novel model of patient engagement that is equity promoting, Equity Mobilizing Partnerships in Community, and extensive experience as patient partners engaged across the healthcare ecosystem. We introduce readers to a new conceptual tool, the Power Wheel, that can be used to analyse the interspersion of power in the places and spaces of patient engagement., Conclusion: As a tool for ongoing praxis (reflection +action), the Power Wheel can be used to report, reflect and resolve power asymmetries in patient-partnered projects, thereby increasing transparency and illuminating opportunities for equitable transformation and social inclusion so that health services can meet the needs and priorities of all people., Competing Interests: Competing interests: AS is a recipient of the Transition to Leadership Stream Career Development Award in Patient-Oriented Research from the Canadian Institutes for Health Research and is a Health Equity Expert Advisor to the Canadian Partnership Against Cancer (CPAC). All other authors declare no competing interests., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Dynamic full-field optical coherence tomography (D-FFOCT) has recently emerged as a label-free imaging tool, capable of resolving cell types and organelles within 3D live samples, whilst monitoring their activity at tens of milliseconds resolution. Here, a D-FFOCT module design is presented which can be coupled to a commercial microscope with a stage top incubator, allowing non-invasive label-free longitudinal imaging over periods of minutes to weeks on the same sample. Long term volumetric imaging on human induced pluripotent stem cell-derived retinal organoids is demonstrated, highlighting tissue and cell organization processes such as rosette formation and mitosis as well as cell shape and motility. Imaging on retinal explants highlights single 3D cone and rod structures. An optimal workflow for data acquisition, postprocessing and saving is demonstrated, resulting in a time gain factor of 10 compared to prior state of the art. Finally, a method to increase D-FFOCT signal-to-noise ratio is demonstrated, allowing rapid organoid screening., (© 2023. Springer Nature Limited.)

Background: There are over 500,000 survivors of childhood cancer in North America alone. One in 4 survivors experiences chronic pain after treatment has been completed. Youths with chronic pain report increased anxiety, depression, activity limitations, and sleep disturbances. An 8-week web-based cognitive behavioral treatment for chronic pain (Web-Based Management of Adolescent Pain [WebMAP]) has demonstrated a reduction in pain in youths but has not yet been explored in survivors., Objective: The objectives of this study are to (1) test the feasibility and acceptability of WebMAP for a sample of survivors with chronic pain and their parents; (2) assess the acceptability of WebMAP using qualitative interviews; (3) assess WebMAP's effect on activity limitations, pain intensity, depression and anxiety symptoms, and sleep disturbances; and (4) assess WebMAP's effect on parent pain catastrophizing and parental response to their child's pain., Methods: A single-arm mixed methods pre-post intervention study design will be used. Participants will be 34 survivors and at least one of their parents or caregivers. Inclusion criteria are (1) a cancer history, (2) current age of 10-17 years, (3) >2 years post treatment or >5 years post diagnosis, (4) pain present over prior 3 months impairing >1 area of daily life and occurring >1 time per month, and (5) computer access with broadband internet. Survivors will complete a pretreatment questionnaire, which will include the following: the Child Activity Limitations Interview, the pain intensity Numerical Rating Scale, Patient-Reported Outcomes Measurement Information System (PROMIS)-Pain Interference, Anxiety, Depression, Insomnia Severity Index, and Adolescent Sleep Wake Scale. Parents will complete the Pain Catastrophizing Scale-Parent Version and the Adult Responses to Child Symptoms. Upon completion of pretreatment questionnaires (T0), survivors will begin WebMAP. After the 8-week intervention, survivors will complete the same measures (T1), and at 3-month follow-up (T2). Posttreatment interviews will be conducted to determine acceptability. Feasibility will be assessed via recruitment and retention rates. Treatment engagement will be measured by number of modules completed. Pre-post outcome data will be assessed using linear mixed models. Qualitative data will be analyzed using thematic analysis. Patient partners will be involved in study design, recruitment, interpretation of results, and knowledge translation., Results: This study has been funded in January 2022. Data collection started in May 2022 and is projected to end in August 2023. We have enrolled 10 participants as of December 2022., Conclusions: Investigating whether WebMAP is useful to survivors will be an important step in improving pain management in this population., Trial Registration: ClinicalTrials.gov NCT05241717; https://clinicaltrials.gov/ct2/show/NCT05241717., International Registered Report Identifier (irrid): DERR1-10.2196/45804., (©Michaela Patton, Linda E Carlson, Melanie Noel, Tonya Palermo, Victoria Forster, Sara Cho, Fiona Schulte. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 01.08.2023.)

Objective: To describe adaptive optics flood illumination ophthalmoscopy (AO-FIO) of the photoreceptor layer in normal nonhuman primates (NHPs) and in the case of a short-term induced retinal detachment (RD)., Design: Longitudinal fundamental research study., Subjects: Four NHPs were used to image normal retinae with AO-FIO (in comparison with 4 healthy humans); 2 NHPs were used to assess the effects of RD., Intervention: The photoreceptor layer (cone mosaic metrics, including cone density, cone spacing, and cone regularity) was followed with AO-FIO imaging (rtx1, Imagine Eyes) during a surgically induced RD in 2 NHPs using a vehicle solution containing dimethyl sulfoxide, classically used as a chemical solvent. We also performed functional testing of the retina (full-field and multifocal electroretinogram [ERG])., Main Outcome Measures: Correlation of cone mosaic metrics (cone density, spacing, and regularity) between normal retinae of NHPs and humans, and cone metrics, power spectrum, and ERG wave amplitudes after RD., Results: Imaging features were very similar in terms of cone reflectivity, cell density, regularity, and spacing values, showing strong positive correlations between NHPs and humans. After RD, AO-FIO revealed several alterations of the cone mosaic slowly recovering during the 3 months after the reattachment, which were not detected functionally by ERG., Conclusions: These results demonstrate by in vivo AO-FIO imaging the transient structural changes of photoreceptors after an RD in the primate retina. They also provide an interesting illustration of the AO-FIO potential for investigating photoreceptor toxicity during preclinical studies in NHPs with a high translatability to human studies., Financial Disclosures: Proprietary or commercial disclosure may be found after the references., (© 2023 by the American Academy of Ophthalmology.)

Retinal melanosome/melanolipofuscin-containing cells (MCCs), clinically visible as hyperreflective foci (HRF) and a highly predictive imaging biomarker for the progression of age-related macular degeneration (AMD), are widely believed to be migrating retinal pigment epithelial (RPE) cells. Using human donor tissue, we identify the vast majority of MCCs as melanophages, melanosome/melanolipofuscin-laden mononuclear phagocytes (MPs). Using serial block-face scanning electron microscopy, RPE flatmounts, bone marrow transplantation and in vitro experiments, we show how retinal melanophages form by the transfer of melanosomes from the RPE to subretinal MPs when the "don't eat me" signal CD47 is blocked. These melanophages give rise to hyperreflective foci in Cd47 -/- -mice in vivo, and are associated with RPE dysmorphia similar to intermediate AMD. Finally, we show that Cd47 expression in human RPE declines with age and in AMD, which likely participates in melanophage formation and RPE decline. Boosting CD47 expression in AMD might protect RPE cells and delay AMD progression., (© 2023. The Author(s).)

Purpose: Diagnosis of Mismatch Repair Deficiency (MMRD) is crucial for tumor management and early detection in patients with the cancer predisposition syndrome constitutional mismatch repair deficiency (CMMRD). Current diagnostic tools are cumbersome and inconsistent both in childhood cancers and in determining germline MMRD., Patients and Methods: We developed and analyzed a functional Low-pass Genomic Instability Characterization (LOGIC) assay to detect MMRD. The diagnostic performance of LOGIC was compared with that of current established assays including tumor mutational burden, immunohistochemistry, and the microsatellite instability panel. LOGIC was then applied to various normal tissues of patients with CMMRD with comprehensive clinical data including age of cancer presentation., Results: Overall, LOGIC was 100% sensitive and specific in detecting MMRD in childhood cancers (N = 376). It was more sensitive than the microsatellite instability panel (14%, P = 4.3 × 10 -12 ), immunohistochemistry (86%, P = 4.6 × 10 -3 ), or tumor mutational burden (80%, P = 9.1 × 10 -4 ). LOGIC was able to distinguish CMMRD from other cancer predisposition syndromes using blood and saliva DNA ( P < .0001, n = 277). In normal cells, MMRDness scores differed between tissues (GI > blood > brain), increased over time in the same individual, and revealed genotype-phenotype associations within the mismatch repair genes. Importantly, increased MMRDness score was associated with younger age of first cancer presentation in individuals with CMMRD ( P = 2.2 × 10 -5 )., Conclusion: LOGIC was a robust tool for the diagnosis of MMRD in multiple cancer types and in normal tissues. LOGIC may inform therapeutic cancer decisions, provide rapid diagnosis of germline MMRD, and support tailored surveillance for individuals with CMMRD.

Introduction: Considerable observational evidence suggests that cancer online support groups reduce feelings of isolation, depression and anxiety, enhance coping and self-management, and lead to better informed patients. Other studies indicate that cancer online support groups can increase distress. Yet no studies theorise the complex, context-dependent mechanisms by which cancer online support groups generate their-sometimes contrasting-outcomes., Methods and Analysis: Guided by an integrated knowledge translation approach and the strategy for patient-oriented research, we will conduct a realist review of cancer online support groups in partnership with stakeholders. We will follow Pawson's five steps and existing quality standards to develop a program theory that explains how cancer online support groups work, for whom and in what circumstances. The specific research questions will be: what positive and negative outcomes have been reported on cancer online support groups? What are the mechanisms that are associated with these outcomes, in which contexts and for whom? Through a rigorous review of relevant scientific and grey literature, as well as ongoing dialogue with stakeholders, a program theory will be developed to explain who benefits from cancer online support groups and who does not, what benefits they derive (or do not), and the factors that affect these outcomes., Ethics and Dissemination: The use of secondary data for this review precludes the need for ethical approval. Dissemination will be informed by the knowledge-to-action framework and will consist of tailored knowledge products that are conceived of collaboratively with stakeholders. These will include peer-reviewed publications on how cancer online support groups can be optimised and best practice recommendations to maximise the benefits experienced by people with cancer. These traditional scientific outputs, along with their respective evidence summaries, will be amplified through strategic social media events hosted and promoted by knowledge users., Prospero Registration Number: CRD42021250046., Competing Interests: Competing interests: GW is deputy chair of the UK’s National Institute for Health Research’s Health Technology Assessment Prioritisation Committee: Integrated Community Health and Social Care (Panel A)., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Vision restoration is an ideal medical application for optogenetics, because the eye provides direct optical access to the retina for stimulation. Optogenetic therapy could be used for diseases involving photoreceptor degeneration, such as retinitis pigmentosa or age-related macular degeneration. We describe here the selection, in non-human primates, of a specific optogenetic construct currently tested in a clinical trial. We used the microbial opsin ChrimsonR, and showed that the AAV2.7m8 vector had a higher transfection efficiency than AAV2 in retinal ganglion cells (RGCs) and that ChrimsonR fused to tdTomato (ChR-tdT) was expressed more efficiently than ChrimsonR. Light at 600 nm activated RGCs transfected with AAV2.7m8 ChR-tdT, from an irradiance of 10 15 photons.cm -2 .s -1 . Vector doses of 5 × 10 10 and 5 × 10 11 vg/eye transfected up to 7000 RGCs/mm 2 in the perifovea, with no significant immune reaction. We recorded RGC responses from a stimulus duration of 1 ms upwards. When using the recorded activity to decode stimulus information, we obtained an estimated visual acuity of 20/249, above the level of legal blindness (20/400). These results lay the groundwork for the ongoing clinical trial with the AAV2.7m8 - ChR-tdT vector for vision restoration in patients with retinitis pigmentosa.

Liposome-supported peritoneal dialysis (LSPD) with transmembrane pH-gradient liposomes was previously shown to enhance ammonia removal in cirrhotic rats and holds promise for the treatment of hyperammonemic crises-associated disorders. The main objective of this work was to conduct the preclinical evaluation of LSPD in terms of pharmacokinetics, ammonia uptake, and toxicology to seek regulatory approval for a first-in-human study. The formulation containing citric acid-loaded liposomes was administered intraperitoneally at two different doses once daily for ten days to healthy minipigs. It was also tested in a domestic pig model of hyperammonemia. The pharmacokinetics of citric acid and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine was linear following intraperitoneal administration of medium and high dose. There was no systemic accumulation following daily doses over ten days. The systemic exposure to phospholipids remained low. Furthermore, the liposome-containing peritoneal fluid contained significantly higher ammonia levels than the liposome-free control, demonstrating efficient ammonia sequestration in the peritoneal space. This was indeed confirmed by the ability of LSPD to decrease plasmatic ammonia levels in artificially induced hyperammonemic pigs. LSPD was well tolerated, and no complement activation-related pseudoallergy reactions were observed. The safety profile, the linear pharmacokinetics of citric acid following repeated administrations of LSPD as well as the linear dose-dependent ammonia sequestration in the peritoneal space provide a strong basis for the clinical investigation of LSPD., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Lighting is rapidly changing with the introduction of light-emitting diodes (LEDs) in our homes, workplaces, and cities. This evolution of our optical landscape raises major concerns regarding phototoxicity to the retina since light exposure is an identified risk factor for the development of age-related macular degeneration (AMD). In this disease, cone photoreceptors degenerate while the retinal pigment epithelium (RPE) is accumulating lipofuscin containing phototoxic compounds such as A2E. Therefore, it remains unclear if the light-elicited degenerative process is initiated in cones or in the RPE. Using purified cone photoreceptors from pig retina, we here investigated the effect of light on cone survival from 390 to 510 nm in 10 nm steps, plus the 630 nm band. If at a given intensity (0.2 mW/cm²), the most toxic wavelengths are comprised in the visible-to-near-UV range, they shift to blue-violet light (425-445 nm) when exposing cells to a solar source filtered by the eye optics. In contrast to previous rodent studies, this cone photoreceptor phototoxicity is not related to light absorption by the visual pigment. Despite bright flavin autofluorescence of cone inner segment, excitation-emission matrix of this inner segment suggested that cone phototoxicity was instead caused by porphyrin. Toxic light intensities were lower than those previously defined for A2E-loaded RPE cells indicating cones are the first cells at risk for a direct light insult. These results are essential to normative regulations of new lighting but also for the prevention of human retinal pathologies since toxic solar light intensities are encountered even at high latitudes.

Vascular endothelial growth factor-A (VEGF) is the angiogenic factor promoting the pathological neovascularization in age-related macular degeneration (AMD) or diabetic macular edema (DME). Evidences have suggested a neurotrophic and neuroprotective role of VEGF, albeit in retina, cellular mechanisms underlying the VEGF neuroprotection remain elusive. Using purified adult retinal ganglion cells (RGCs) in culture, we demonstrated here that VEGF is released by RGCs themselves to promote their own survival, while VEGF neutralization by specific antibodies or traps drastically reduced the RGC survival. These results indicate an autocrine VEGF neuroprotection on RGCs. In parallel, VEGF produced by mixed retinal cells or by mesenchymal stem cells exerted a paracrine neuroprotection on RGCs. Such neuroprotective effect was obtained using the recombinant VEGF-B, suggesting the involvement of VEGF-R1 pathway in VEGF-elicited RGC survival. Finally, glaucomatous patients injected with VEGF traps (ranibizumab or aflibercept) due to either AMD or DME comorbidity, showed a significant reduction of RGC axon fiber layer thickness, consistent with the plausible reduction of the VEGF autocrine stimulation of RGCs. Our results provide evidence of the autocrine neuroprotective function of VEGF on RGCs is crucially involved to preserve injured RGCs such as in glaucomatous patients.

Retinal dystrophies and age-related macular degeneration related to photoreceptor degeneration can cause blindness. In blind patients, although the electrical activation of the residual retinal circuit can provide useful artificial visual perception, the resolutions of current retinal prostheses have been limited either by large electrodes or small numbers of pixels. Here we report the evaluation, in three awake non-human primates, of a previously reported near-infrared-light-sensitive photovoltaic subretinal prosthesis. We show that multipixel stimulation of the prosthesis within radiation safety limits enabled eye tracking in the animals, that they responded to stimulations directed at the implant with repeated saccades and that the implant-induced responses were present two years after device implantation. Our findings pave the way for the clinical evaluation of the prosthesis in patients affected by dry atrophic age-related macular degeneration.

The mammalian retina contains multiple cellular layers, each carrying out a specific task. Such a controlled organization should be considered as a crucial factor for designing retinal therapies. The maintenance of retinal layered complexity through the use of scaffold-free techniques has recently emerged as a promising approach for clinical ocular tissue engineering. In an attempt to fabricate such layered retinal model, we are proposing herein a unique inkjet bioprinting system applied to the deposition of a photoreceptor cells (PRs) layer on top of a bioprinted retinal pigment epithelium (RPE), in a precise arrangement and without any carrier material. The results showed that, after bioprinting, both RPE and PRs were well positioned in a layered structure and expressed their structural markers, which was further demonstrated by ZO1, MITF, rhodopsin, opsin B, opsin R/G and PNA immunostaining, three days after bioprinting. We also showed that considerable amounts of human vascular endothelial growth factors (hVEGF) were released from the RPE printed layer, which confirmed the formation of a functional RPE monolayer after bioprinting. Microstructures of bioprinted cells as well as phagocytosis of photoreceptor outer segments by apical RPE microvilli were finally established through transmission electron microscopy (TEM) imaging. In summary, using this carrier-free bioprinting method, it was possible to develop a reasonable in vitro retina model for studying some sight-threatening diseases, such as age-related macular degeneration (AMD) and retinitis pigmentosa (RP).

Background: Age-related macular degeneration is characterized by the accumulation of subretinal macrophages and the degeneration of cones, but mainly of rods. We have previously shown that Mononuclear Phagocytes-derived IL-1β induces rod photoreceptor cell death during experimental subretinal inflammation and in retinal explants exposed to IL-1β but the mechanism is unknown., Methods: Retinal explants were culture in the presence of human monocytes or IL-1β and photoreceptor cell survival was analyzed by TUNEL labeling. Glutamate concentration and transcription levels of gene involved in the homeostasis of glutamate were analyzed in cell fractions of explant cultured or not in the presence of IL-1β. Glutamate receptor antagonists were evaluated for their ability to reduce photoreceptor cell death in the presence of IL1-β or monocytes., Results: We here show that IL-1β does not induce death in isolated photoreceptors, suggesting an indirect effect. We demonstrate that IL-1β leads to glutamate-induced rod photoreceptor cell death as it increases the extracellular glutamate concentrations in the retina through the inhibition of its conversion to glutamine in Müller cells, increased release from Müller cells, and diminished reuptake. The inhibition of non-NMDA receptors completely and efficiently prevented rod apoptosis in retinal explants cultured in the presence of IL-1β or, more importantly, in vivo, in a model of subretinal inflammation., Conclusions: Our study emphasizes the importance of inflammation in the deregulation of glutamate homeostasis and provides a comprehensive mechanism of action for IL-1β-induced rod degeneration.

Objectives: Bone and soft-tissue calcifications are often coincidentally diagnosed on digital panoramic radiographs (DPRs). As the use of three-dimensional (3D) images has increased in the past decade for diagnostics in the mandibular region, we evaluated 3D volume images derived from 2D panoramic images to determine if this method is suitable for early detection of calcifications in this region., Methods: In this study, three investigators retrospectively and independently evaluated 822 DPRs. If one or more calcifications were present, the 3D volume image from that patient was retrospectively evaluated to confirm the incidental findings. A radiographic system with a low-dose mode and a high-resolution 3D-image function was used. The investigators focussed on the most common calcifications, including tonsilloliths (TL), idiopathic osteosclerosis (IO) of the mandible, carotid artery calcifications (CAC), calcified submandibular lymph nodes (hereafter, CSL), and sialoliths of the submandibular salivary gland (SSG)., Results: One or more calcifications were identified in 415 (50.5%) DPRs. In total, 718 calcifications were detected, 30.2% of which were TL, 16.3% IO, 11.3% CAC, 8.8% CSL, and 1.7% SSG. Only 287 (39.97 %) of the calcifications were confirmed on 3D volume images; of these, 29.2% were TL, 58.5% IO, 0.2% CAC, and 1.4% SSG. No CSLs were detected., Conclusions: Not all areas shown on the DPRs were visible in the retrospectively obtained 3D volume images. Whereas DPRs are used to diagnose calcifications such as IO, TL, SSG, CAC, and CSL, the 3D volume images were only useful for confirming the existence of IO, TL, and SSG calcifications.

Oncogenic transcription factors such as the leukemic fusion protein RUNX1/ETO, which drives t(8;21) acute myeloid leukemia (AML), constitute cancer-specific but highly challenging therapeutic targets. We used epigenomic profiling data for an RNAi screen to interrogate the transcriptional network maintaining t(8;21) AML. This strategy identified Cyclin D2 (CCND2) as a crucial transmitter of RUNX1/ETO-driven leukemic propagation. RUNX1/ETO cooperates with AP-1 to drive CCND2 expression. Knockdown or pharmacological inhibition of CCND2 by an approved drug significantly impairs leukemic expansion of patient-derived AML cells and engraftment in immunodeficient murine hosts. Our data demonstrate that RUNX1/ETO maintains leukemia by promoting cell cycle progression and identifies G1 CCND-CDK complexes as promising therapeutic targets for treatment of RUNX1/ETO-driven AML., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)

Peritoneal dialysis (PD) performed with transmembrane pH-gradient liposomes was reported to efficiently remove ammonia from the body, representing a promising alternative to current standard-of-care for patients with severe hepatic encephalopathy. In this study, we further characterized the properties of liposome-supported peritoneal dialysis (LSPD) by 1) assessing its in-use stability in the presence of ascitic fluids from liver-disease patients; 2) investigating its interactions with drugs that are commonly administered to acute-on-chronic liver failure patients; and 3) analyzing the in vivo extraction profile of LSPD. We found that LSPD fluid maintained its in vitro ammonia uptake capability when combined with ascitic fluids. The co-incubation of selected drugs (e.g., beta-blockers, antibiotics, diuretics) with LSPD fluids and ammonia resulted in limited interaction effects for most compounds except for two fluoroquinolones and propranolol. However, considering the experimental set-up, these results should be interpreted with caution and confirmatory drug-drug interaction studies in a clinical setting will be required. Finally, metabolite-mapping analysis on dialysates of LSPD-treated rats revealed that the liposomes did not remove important metabolites more than a conventional PD fluid. Overall, these findings confirm that LSPD is a potentially safe and effective approach for treating hyperammonemic crises in the context of acute-on-chronic liver failure., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The retinal pigment epithelium (RPE) is a monolayer of pigmented cells with important barrier and immuno-suppressive functions in the eye. We have previously shown that acute stimulation of RPE cells by tumor necrosis factor alpha (TNFα) downregulates the expression of OTX2 (Orthodenticle homeobox 2) and dependent RPE genes. We here investigated the long-term effects of TNFα on RPE cell morphology and key functions in vitro., Methods: Primary porcine RPE cells were exposed to TNFα (at 0.8, 4, or 20 ng/ml per day) for 10 days. RPE cell morphology, phagocytosis, barrier- and immunosuppressive-functions were assessed., Results: Chronic (10 days) exposure of primary RPE cells to TNFα increases RPE cell size and polynucleation, decreases visual cycle gene expression, impedes RPE tight-junction organization and transepithelial resistance, and decreases the immunosuppressive capacities of the RPE. TNFα-induced morphological- and transepithelial-resistance changes were prevented by concomitant Transforming Growth Factor β inhibition., Conclusions: Our results indicate that chronic TNFα-exposure is sufficient to alter RPE morphology and impede cardinal features that define the differentiated state of RPE cells with striking similarities to the alterations that are observed with age in neurodegenerative diseases such as age-related macular degeneration.

Intraocular injection of adeno-associated viral (AAV) vectors has been an evident route for delivering gene drugs into the retina. However, gaps in our understanding of AAV transduction patterns within the anatomically unique environments of the subretinal and intravitreal space of the primate eye impeded the establishment of noninvasive and efficient gene delivery to foveal cones in the clinic. Here, we establish new vector-promoter combinations to overcome the limitations associated with AAV-mediated cone transduction in the fovea with supporting studies in mouse models, human induced pluripotent stem cell-derived organoids, postmortem human retinal explants, and living macaques. We show that an AAV9 variant provides efficient foveal cone transduction when injected into the subretinal space several millimeters away from the fovea, without detaching this delicate region. An engineered AAV2 variant provides gene delivery to foveal cones with a well-tolerated dose administered intravitreally. Both delivery modalities rely on a cone-specific promoter and result in high-level transgene expression compatible with optogenetic vision restoration. The model systems described here provide insight into the behavior of AAV vectors across species to obtain safety and efficacy needed for gene therapy in neurodegenerative disorders.

Compared to hemodialysis, peritoneal dialysis represents a more straightforward and less invasive alternative, though current solutions are not as effective. Herein, the feasibility of liposome-supported enzymatic peritoneal dialysis (LSEPD) is explored to increase the functionality of peritoneal dialysis for the model indication acute alcohol poisoning. Enzyme-loaded liposomes (E-Liposomes) containing alcohol metabolizing enzymes, alcohol oxidase and catalase, are developed and their in vitro and in vivo performances investigated. The E-Liposomes outperform the free enzymes in stability, overcoming the thermal instability of alcohol oxidase and enhancing the in vitro ethanol elimination, which is further accelerated by hydrogen peroxide, due to the rapid generation of oxygen by catalase. Compared to the free enzymes, the E-Liposomes exhibit reduced systemic exposure and organ distribution. In a rodent ethanol intoxication model, LSEPD enhances ethanol metabolism as evidenced by an increased acetaldehyde production, ethanol's primary metabolite. In conclusion, LSEPD presents an innovative platform to temporarily enhance xenobiotic metabolism, in view of the improved enzyme stability and peritoneal retention., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Retinal gene delivery via intravitreal injection is hampered by various physiological barriers present in the eye of which the vitreoretinal (VR) interface represents the most serious hurdle. In this study, we present a retinal explant model especially designed to study the role of this interface as a barrier for the penetration of vectors into the retina. In contrast to all existing explant models, the developed model is bovine-derived and more importantly, keeps the vitreous attached to the retina at all times to guarantee an intact VR interface. After ex vivo intravitreal injection into the living retinal explant, the route of fluorescent carriers across the VR interface can be tracked. By applying two different imaging methods on this model, we discovered that the transfer through the VR barrier is size-dependent since 40 nm polystyrene particles are more easily taken up in the retina than 100 and 200 nm sized particles. In addition, we found that removing the vitreous, as commonly done for culture of conventional explants, leads to an overestimation of particle uptake, and conclude that the ultimate barrier to overcome for retinal uptake is undoubtedly the inner limiting membrane. Damaging this matrix resulted in a massive increase in particle transfer into the retina. In conclusion, we have developed a highly relevant ex vivo model that maximally mimics the human in vivo physiology which can be applied as a representative test set-up to assess the potential of promising drug delivery carriers to cross the VR interface.