| 1. |
- Al-Hawasi, Abbas, 1976-
(författare)
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Retinal ganglion cell examination with Optical Coherence Tomography reflects physiological and pathological changes in the eye and the brain.
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The retinal ganglion cell is situated in the inner retina and its axons, composing the retinal nerve fiber layer (RNFL), leave the eye to form the optic nerve. These cells develop embryologically from the forebrain and later during development re-establish connections with different parts of the brain serving different purposes. This unique position and connections make it possible to be investigated with different methods. Optical Coherence Tomography (OCT) is an accessible and easily operated clinical device that can provide a detailed image of this layer at a few micrometers level of precision in measurements. In this thesis we aimed to see whether examining these cells with OCT could reflect physiological and pathological changes in the eye and brain.In cases of optic neuritis (Paper I), the OCT examination showed early thickening of the peripapillary (pRNFL) followed by thinning which takes 6-9 months to reduce to below normal thickness without the ability to distinguish between the real from pseudo thinning. The ganglion cell -inner plexiform layer (GCL-IPL) layer, however, showed a thickness reduction within a few weeks to 3 months without pseudo thinning. In cases of Idiopathic Intracranial Hypertension (IIH) (Paper II), the GCL-IPL remained unchanged and there was no difference in pRNFL thickness compared to healthy controls, whereas the optic disc parameters of rim thickness, rim area, cup volume and cup/disc ratio differed significantly (P<0.05).In cases of benign multiple sclerosis (Paper IV), the OCT could detect that eyes which are not affected by optic neuritis had an annual thinning rate of the RNFL and GCL-IPL similar to a healthy population (P>0.05) which may indicate the benign course of the disease. In cases of physiological factors affecting the GCL in healthy population (Paper III) the OCT examination showed that there was a significant thinning rate of the layer with age (P<0.05), but the thinning was not significant when sex and axial length of the eye were taken into consideration. Males had a thicker GCL volume than females and with age a significant reduction in GCL volume was noted in females but not in males. A Longer axial length of the eye found to be associated with thinner GCL volume. In conclusion retinal ganglion cell changes detected with OCT can reflect physiological and pathological changes in the eye and brain.
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| 2. |
- Al-Hawasi, Abbas, et al.
(författare)
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Longitudinal Optical Coherence Tomography Measurement of Retinal Ganglion Cell and Nerve Fiber Layer to Assess Benign Course in Multiple Sclerosis
- 2023
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- A benign form of multiple sclerosis (BMS) is not easily diagnosed, but changes of the retinal ganglion cell layer-inner plexiform layer (GCL-IPL) and retinal nerve fiber layer (RNFL) may be sensitive to the disease. The aim of this study was to use optical coherence tomography (OCT) to investigate longitudinal changes of GCL-IPL and RNFL in BMS. Eighteen patients with BMS and 22 healthy control (HC) subjects were included, with a mean follow-up period of 32.1 months in BMS and 34.3 months in HC. Mean disease duration in BMS was 23.3 years, with 14 patients left untreated. Unilateral optic neuritis (ON) was found in eight patients. Non-ON eyes showed thinner GCL-IPL layer in the BMS group relative to HC (p < 0.001). The thinning rate of GCL-IPL in non-ON BMS, however, was -0.19 +/- 0.15 mu m/year vs. 0 +/- 0.11 mu m/year for HC (p = 0.573, age-adjusted). Thinning rate of RNFL in non-ON BMS was -0.2 +/- 0.27 mu m/year vs. -0.05 +/- 0.3 mu m/year for HC (p = 0.454, age adjusted). Conclusions: Thinning rate of the GCL-IPL and RNFL in BMS is similar to the healthy population but differs from the thinning rate in relapsing-remitting MS, presenting a non-invasive OCT-based criterion for assessing a benign course in multiple sclerosis.
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| 3. |
- Buznyk, Oleksiy, et al.
(författare)
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Collagen-based scaffolds with infused anti-VEGF release system as potential cornea substitute for high-risk keratoplasty: A preliminary in vitro evaluation
- 2020
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Ingår i: Heliyon. - : ELSEVIER SCI LTD. - 2405-8440. ; 6:10
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Tidskriftsartikel (refereegranskat)abstract
- Currently the only widely accepted corneal blindness treatment is human donor cornea transplantation. However, increasing shortage of donor corneas as well as high risk of rejection in some corneal diseases remain two major problems, which limit the success of corneal transplantation. Corneal neovascularization is considered as one of the main risk factors of graft failure. Different cell-free biosynthetic scaffolds fabricated from collagens or collagen-like peptides are being tested as donor cornea substitutes (DCS). Here, we report for the first-time composite biosynthetic DCS with integrated sustained release system of anti-VEGF drug, bevacizumab and their preliminary in vitro validation. We have tethered gold nanoparticles with bevacizumab and integrated into a collagen-based cell-free hydrogel scaffold. Developed grafts preserved good optical properties and were confirmed not toxic to human corneal epithelial cells. Bevacizumab has been shown to constantly releasing from the DCS up to 3 weeks and preserved its anti-angiogenic properties. These results provide background for further use of infused composite biosynthetic DCS with integrated nanosystem of bevacizumab sustained release in corneal disease accompanied by neovascularisation where conventional corneal transplantation might fail.
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| 4. |
- Fagerholm, Anna-Sara, 1978-, et al.
(författare)
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Activism online : Exploring how crises are communicated visually in activism campaigns
- 2023
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Ingår i: Journal of Contingencies and Crisis Management. - : Wiley. - 0966-0879 .- 1468-5973. ; 31:4, s. 1034-1043
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Tidskriftsartikel (refereegranskat)abstract
- During the past years, activist movements have increasingly turned to social media to raise awareness and critically discuss current development and future scenarios. As a contribution to the discussion of new social movements and activism in the digital age, this study aims to explore and critically discuss how environmental risks and crisis are visually communicated in activism campaigns on Instagram, through a case study on Extinction Rebellion Sweden (XRsv). The study is delimited to the first 334 posts on XRsv's Instagram between November 14, 2018 and March 1, 2020. Methods used are interview and content analysis. In conclusion, XRsv has adopted aspects of design activism including visual tactics of Informing, Activating and Explaining. These three visual aspects are used by XRsv in an online context enabling interactivity and participatory actions, which in turn forms the core of design activism.
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| 5. |
- Fagerholm, Anna-Sara, 1978-, et al.
(författare)
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What a Waste – A norm-critical design study on how waste is understood and managed
- 2023
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Ingår i: Resources, Conservation & Recycling Advances. - : Elsevier BV. - 2667-3789. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- This article seeks to contribute new insights into inclusive recycling environments through universal design. The aim is to develop knowledge on how waste is understood and managed by exploring the practice and design of a recycling environment. Applying a norm-critical view, this is explored in a study with participants from a municipal housing company and waste management company in northern Sweden. Methods used are go-along interviews together with professionals and observations of a recycling environment. The results are discussed as: 1) the “(un)social norm;” where our results show that the waste system is perceived as a social system, contradicting previous approaches where waste systems are treated as technical environments. 2) the “(un)design factor;” where we identify how design in a recycling context that doesn´t emphasise diversity may affect activities of sorting.
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| 6. |
- Fagerholm, Anna-Sara, 1978-, et al.
(författare)
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What a Waste – A norm-critical study on how waste is understood and managed through integrating perspectives
- 2022
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Ingår i: Book of Abstracts – The 28th Annual Conference, International Sustainable Development Research Society “Sustainable Development and Courage. Culture, Art and Human Rights” 15-17 june 2022. ; , s. 252-253
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Konferensbidrag (refereegranskat)abstract
- In previous research waste is described as a design flaw, as the processes that generate waste are a result of poor design (Anastas & Zimmerman, 2006; Ordónez, 2017). Ekberg (2009) points out that waste is what is left behind when imagination fails and this also reflects a reconsidering of waste as resources if given another context. In a globalized world with international trade, there is a greater range of products on the market and the amount of waste is constantly increasing (Avfall Sverige, 2021). A challenge is therefore to reduce the amount of waste. De Laney (2018) points out that there is a huge opportunity to reduce landfill waste and improve consumer habits through design. In this process, we must learn to include new and more inclusive ways of thinking and acting that support long-term social sustainability through design (Wikberg Nilsson & Jahnke, 2018). More than forty years ago, Dilnot (1982) emphasized that through design, we humans give shape, direction and meaning to our individual and collective existence in the world. Today, there are different design solutions for household waste and recycling and Vollaard and van Soest (2020) argue that reducing unsorted waste normally requires little in the way of capital investment beyond buying a set of in-home recycling bins. Although, many times consumers aren´t aware of the impact of their disposal decisions and many facilities for local waste disposal and recycling have processes that are unique to them that could cause confusion (De Laney, 2018). In accordance, we must find a way to get consumers to care and to motivate a change in habits. The research question of this study is how waste is understood and managed and this is explored through a case study with a local housing company and waste management company, interested in improving waste sorting. In order to answer the research question, interviews are conducted with people living in the specific buildings belonging to the housing company, respondents from the local housing company and the waste management company and results are presented on perceptions of waste and what the barriers are to improve waste sorting. This is complemented by a literature review to provide a better understanding of research through design for a sustainable behavior related to waste. This paper presents a norm-critical aspect on universal design and waste in a collaborative research project with the objective of creating more inclusive solutions for waste systems. The overall ambition of this study is to build on knowledge of the role of design as an activity of shaping the human surroundings and as an expression of the culture to which it belongs (Skjerven & Reitan, 2018). The study is related to global goal number 2.5: by 2030, substantially reduce waste generation through prevention, reduction, recycling and reuse.
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| 7. |
- Haagdorens, Michel, et al.
(författare)
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Plant Recombinant Human Collagen Type I Hydrogels for Corneal Regeneration
- 2022
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Ingår i: REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE. - : Springer Berlin/Heidelberg. - 2364-4133 .- 2364-4141. ; 8:2, s. 269-283
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Tidskriftsartikel (refereegranskat)abstract
- Purpose To determine feasibility of plant-derived recombinant human collagen type I (RHCI) for use in corneal regenerative implantsMethods RHCI was crosslinked with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) to form hydrogels. Application of shear force to liquid crystalline RHCI aligned the collagen fibrils. Both aligned and random hydrogels were evaluated for mechanical and optical properties, as well as in vitro biocompatibility. Further evaluation was performed in vivo by subcutaneous implantation in rats and corneal implantation in Gottingen minipigs.Results Spontaneous crosslinking of randomly aligned RHCI (rRHCI) formed robust, transparent hydrogels that were sufficient for implantation. Aligning the RHCI (aRHCI) resulted in thicker collagen fibrils forming an opaque hydrogel with insufficient transverse mechanical strength for surgical manipulation. rRHCI showed minimal inflammation when implanted subcutaneously in rats. The corneal implants in minipigs showed that rRHCI hydrogels promoted regeneration of corneal epithelium, stroma, and nerves; some myofibroblasts were seen in the regenerated neo-corneas.Conclusion Plant-derived RHCI was used to fabricate a hydrogel that is transparent, mechanically stable, and biocompatible when grafted as corneal implants in minipigs. Plant-derived collagen is determined to be a safe alternative to allografts, animal collagens, or yeast-derived recombinant human collagen for tissue engineering applications. The main advantage is that unlike donor corneas or yeast-produced collagen, the RHCI supply is potentially unlimited due to the high yields of this production method. Lay Summary A severe shortage of human-donor corneas for transplantation has led scientists to develop synthetic alternatives. Here, recombinant human collagen type I made of tobacco plants through genetic engineering was tested for use in making corneal implants. We made strong, transparent hydrogels that were tested by implanting subcutaneously in rats and in the corneas of minipigs. We showed that the plant collagen was biocompatible and was able to stably regenerate the corneas of minipigs comparable to yeast-produced recombinant collagen that we previously tested in clinical trials. The advantage of the plant collagen is that the supply is potentially limitless.
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| 8. |
- Malhotra, Kamal, et al.
(författare)
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Phosphorylcholine and KR12-Containing Corneal Implants in HSV-1-Infected Rabbit Corneas
- 2023
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Ingår i: Pharmaceutics. - : MDPI. - 1999-4923 .- 1999-4923. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- Severe HSV-1 infection can cause blindness due to tissue damage from severe inflammation. Due to the high risk of graft failure in HSV-1-infected individuals, cornea transplantation to restore vision is often contraindicated. We tested the capacity for cell-free biosynthetic implants made from recombinant human collagen type III and 2-methacryloyloxyethyl phosphorylcholine (RHCIII-MPC) to suppress inflammation and promote tissue regeneration in the damaged corneas. To block viral reactivation, we incorporated silica dioxide nanoparticles releasing KR12, the small bioactive core fragment of LL37, an innate cationic host defense peptide produced by corneal cells. KR12 is more reactive and smaller than LL37, so more KR12 molecules can be incorporated into nanoparticles for delivery. Unlike LL37, which was cytotoxic, KR12 was cell-friendly and showed little cytotoxicity at doses that blocked HSV-1 activity in vitro, instead enabling rapid wound closure in cultures of human epithelial cells. Composite implants released KR12 for up to 3 weeks in vitro. The implant was also tested in vivo on HSV-1-infected rabbit corneas where it was grafted by anterior lamellar keratoplasty. Adding KR12 to RHCIII-MPC did not reduce HSV-1 viral loads or the inflammation resulting in neovascularization. Nevertheless, the composite implants reduced viral spread sufficiently to allow stable corneal epithelium, stroma, and nerve regeneration over a 6-month observation period.
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| 9. |
- McTiernan, Christopher D., et al.
(författare)
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LiQD Cornea: Pro-regeneration collagen mimetics as patches and alternatives to corneal transplantation
- 2020
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Ingår i: Science Advances. - : AMER ASSOC ADVANCEMENT SCIENCE. - 2375-2548. ; 6:25
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Tidskriftsartikel (refereegranskat)abstract
- Transplantation with donor corneas is the mainstay for treating corneal blindness, but a severe worldwide shortage necessitates the development of other treatment options. Corneal perforation from infection or inflammation is sealed with cyanoacrylate glue. However, the resulting cytotoxicity requires transplantation. LiQD Cornea is an alternative to conventional corneal transplantation and sealants. It is a cell-free, liquid hydrogel matrix for corneal regeneration, comprising short collagen-like peptides conjugated with polyethylene glycol and mixed with fibrinogen to promote adhesion within tissue defects. Gelation occurs spontaneously at body temperature within 5 min. Light exposure is not required-particularly advantageous because patients with corneal inflammation are typically photophobic. The self-assembling, fully defined, synthetic collagen analog is much less costly than human recombinant collagen and reduces the risk of immune rejection associated with xenogeneic materials. In situ gelation potentially allows for clinical application in outpatient clinics instead of operating theaters, maximizing practicality, and minimizing health care costs.
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| 10. |
- Rafat, Mehrdad, et al.
(författare)
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Bioengineered corneal tissue for minimally invasive vision restoration in advanced keratoconus in two clinical cohorts
- 2023
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Ingår i: Nature Biotechnology. - : Nature Portfolio. - 1087-0156 .- 1546-1696. ; 41:1, s. 70-81
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Tidskriftsartikel (refereegranskat)abstract
- Visual impairment from corneal stromal disease affects millions worldwide. We describe a cell-free engineered corneal tissue, bioengineered porcine construct, double crosslinked (BPCDX) and a minimally invasive surgical method for its implantation. In a pilot feasibility study in India and Iran (clinicaltrials.gov no.NCT04653922), we implanted BPCDX in 20 advanced kera- toconus subjects to reshape the native corneal stroma without removing existing tissue or using sutures. During 24 months of follow-up, no adverse event was observed. We document improvements in corneal thickness (mean increase of 209 +/- 18 mu m in India, 285 +/- 99 um in Iran), maximum keratometry (mean decrease of 13.9 +/- 7.9 D in India and 11.2 +/- 8.9 D in Iran) and visual acuity (to a mean contact-lens-corrected acuity of 20/26 in India and spectacle-corrected acuity of 20/58 in Iran). Fourteen of 14 initially blind subjects had a final mean best-corrected vision (spectacle or contact lens) of 20/36 and restored tolerance to contact lens wear. This work demonstrates restoration of vision using an approach that is potentially equally effective, safer, simpler and more broadly available than donor cornea transplantation.
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