Animal experimentation: the chicken model in myopia research

The following article is presented to you by Sandra Gisbert Martinez
Disclaimer: The following text may content specific terms, requiring more in deep knowledge in the field.

 

Animal experiments are essential for the progress of basic and applied biological and medical research since many fundamental questions cannot be solved purely by epidemiological approaches in human studies. In particular in myopia, which represents the result of complex interactions of environmental and genetic factors, basic questions cannot be answered only in human studies, like “which visual cues make eyes myopic?” or “which biochemical changes occur in the fundal layers when the eye starts growing longer?” or “why and how do certain drugs inhibit myopia development and could they be used to inhibit myopia in humans?”

What is animal experimentation?

The Animal Welfare Act ensures the protection of animals, which are predetermined to use in animal experiments or whose tissue or organs shall be used for scientific purposes. Any procedure carried out on animals for scientific purposes must be monitored and approved by the competent authority. The approval process requires accurate information about the purpose of using animals as well as their living and care conditions are examined. As you can observe, the aim of the law is to protect the life and well-being of the animal.

What is 3Rs principle?

For those who know the topic of animal experimentation, have probably heard of the 3Rs principle which came from the English terms “Reduction – Replacement – Refinement” defined by W. Rusell and R. Burch. It is very important to keep this principle in mind and take it as a guideline because any researcher planning to use animals in their research must justify that there are good ethical, scientific, legal and economic reasons for making sure that animals are looked after properly and used in minimum numbers.

It is necessary fully satisfying the meaning of the 3Rs:

  • Reduction: reduce the number of animals used to a minimum but as many as necessary are used.
  • Replacement: it seeks to substitute animal experiments with alternative methods as much as possible, or to avoid them completely.
  • Refinement: refine the way experiments are carried out, to make sure animals suffer as little as possible. This includes better housing and improvements to procedures which minimize pain and suffering and/or improve animal welfare.
What about experimental animals in myopia research?

It has been reported that genetic factors together with environmental interaction contribute to increase the probability of becoming myopic, nevertheless it is possible that the genetic explanation of myopia would still dominate at that days if animal experiments had not introduced new evidence about mechanisms involved in emmetropisation. The most striking finding showed that placing in front of the eyes spectacle lenses (positive or negative), they can alter their refractive state compensating the defocus imposed by increasing or slowing their rates of axial elongation, and this was observed in chickens, fish, tree shrews, marmosets, rhesus monkeys and guinea pigs (1-5). This fact provides the evidence that there existed a homeostatic mechanism that regulated refractive error. Whereby, it arises a central question as how visual feedback influences axial eye growth.

Why chicken model is suitable for myopia research?

Chicken model was introduced by Wallman, Turkel and Trachtman and today still remains one of the major models for myopia (6). Many of its characteristics are what make it an attractive model for myopia research. Within these features are included (7):

  • Eye size, relatively large (8 to 14mm).
  • Eye growth faster than in other animal species studied (about 100µm/day).
  • Highly sensitive control of refractive state by retinal image quality and focus.
  • Excellent optics.
  • Active accommodation (about 17D).
  • High visual acuity (7cycles/degree).
  • Easy to deliver drugs by intravitreal injection.
  • Easy to handle them.
  • Inexpensive and easy cares.

 

Nevertheless, they also have some disadvantages such as the lack of a fovea, differences in scleral composition or a different mechanism of accommodation compared to mammals.

In spite of that, chicks provided fundamental information on the mechanisms of emmetropization, and still many experiments are carried out on them in order to try to understand which variables in the eye really determine growth rates during myopia progression.


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  • References.
1) Schaeffel F, Glasser A, Howland HC. (1988) Accommodation, refractive error and eye growth in chickens. Vision Res 28: 639–657.

2) Hung LF, Crawford ML, Smith EL. (1995) Spectacle lenses alter eye growth and the refractive status of young monkeys. Nature Med 1: 761–765.

3) Whatham AR, Judge SJ. (2001) Compensatory changes in eye growth and refraction induced by daily wear of soft contact lenses in young marmosets. Vision Res 41: 267–273.

4) Shen W, Sivak JG. (2007) Eyes of a lower vertebrate are susceptible to the visual environment. Invest Ophthalmol Vis Sci 48: 4829–4837.

5) Metlapally S, McBrien NA. (2008) The effect of positive lens defocus on ocular growth and emmetropization in the tree shrew. J Vis 8(1): 1–12. 12. Howlett M, McFadden S. (2009) Spectacle lens compensation in the pigmented guinea pig. Vision Res 49: 219–227.

6) Wallman J, Turkel J, Trachtman J. (1978) Extreme myopia produced by modest change in earlyvisual experience. Science 201(4362): 1249-51.

7) Schaeffel F, Feldkaemper M. (2015) Animal models in myopia research. Clin Exp Optom;98(6):507-17
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Second MYFUN annual meeting

The following article is presented to you by Dibyendu Pusti
For all the general public.

The 2nd MYFUN annual meeting had been hosted jointly by Laboratorio de Optica (LOUM) and Voptica SL at Universidad de Murcia, Murcia, Spain. The four days event started from 24th October with research work presentation by all MYFUN fellows and thought-provoking lectures by Ph.D. supervisors and invited speakers. The principal investigator of LOUM, Prof. Pablo Artal inaugurated the meeting by welcoming all MYFUN fellows, principal investigators, external advisory board, invited guests and all in-house Lab members. Prof. Frank Schaeffel (Principal investigator of Institute for Ophthalmic Research, EKUT) continued the meeting with his talk regarding management & coordination of MyFUN. All the Early Stage Researchers (ESR) presented their research work and had intense discussion with senior researchers and external advisory board members throughout first two days. Beside interesting scientific discussion by ESRs, keynote speakers enlightened the forum with their presentations. Prof. Denis Pelli (New York University, USA) delivered his talk about the sources of noise in human vision and Dr. Ireneusz Grulkowski (Copernicus University, Torun, Poland) shared his expert views on the advances of OCT for the eye.

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The Summer school started on the second day afternoon, which was similarly fascinating where many legendary scientists shared their years of experience and knowledge. After formal inauguration and welcome ceremony by Rosa Miras from Voptica, Prof. Susana Marcos (CSIS, Madrid) started the session with her views on latest development in ocular photo-activated treatment. The day continued with talks on crowding phenomena and pharmacological management of myopia by Prof. Denis Pelli and Prof. Christine Wildsoet (Berkeley, USA) respectively. The next day continued with motivating lecture sessions by Prof. Frank Schaeffel, Dr. Ireneusz Grulkowski, Dr. Linda Lundstroem (KTH, Stockholm), Dr. Brian Vohnsen (UCD, Dublin), Dr. Juan Tabernero (Cambridge, UK), Dr. Marita Feldkaemper (EKUT, Tübingen) and Prof. Donald Mutti (Columbus, USA). End of the day, Prof. Pablo Artal shared his expertise on compensation mechanism in the human eye. Beside the scientific talks, Dr. Guillermo Pérez (J&J Vision, Groningen, NL) shared his immense experience to discuss the Pros and cons of academic and industrial research careers. During the last day of summer school Dr. Pedro Prieto and Dr. Josua Fernández from LOUM, Murcia, shared their proficient scientific expertise about principal and application of adaptive optics in vision science.

All MYFUN fellows visited the LOUM Lab setups, where they went through all the investigation setups thoroughly. All members also got the opportunity to visit Voptica SL manufacturing facility that is situated at the University campus. During the industry visit, Dr. Eloy Villegas & Lucía Hervellá conducted hands-on session of the Visual Adaptive Optics (VAO) simulator. Luis Gómez and Nicolai Suchkov demonstrated the manufacturing unit at Voptica to the ESRs. Prof. Artal concluded the meeting after thanking board members, invited guest speakers, research supervisors, all MYFUN fellows, LOUM members and specially to Carmen Martínez (Project Manager, LOUM) for arranging the whole meeting and logistics efficiently.

Moreover, all the invitees and Lab members enjoyed additional activities with the real flavor of Spanish tradition and delicious local food. They enjoyed the fabulous natural harbor and historical monuments of Cartagena City (a port city and naval base in the Murcia region) during a Guided Tour followed by traditional Spanish dinner at La Pequeña Taberna. During the last evening, a gala dinner was also arranged at the Real Casino de Murcia, which has a traditional restaurant, private social club & culture center in a 19th-century building with an elaborate, grand facade.

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Save the date! Free Webinar on Myopia

OSA Webinar “Solving the Myopia Puzzle” Dec. 15th 2017 @10am EST

We are pleased to announce the 4th webinar hosted by the Applications of Visual Science Technical Group below the Optical Society of America. This webinar will have presentations by Prof. Christine Wildsoet (UC Berkeley), Prof. Frank Schaeffel (U Tübingen) and Prof. Donald Mutti (Ohio State U) who are all leading experts in myopia. The presenters will discuss current understanding of myopia, reasons why myopia is on the rise, and possible steps that can reduce or delay the onset of myopia.

To register for the FREE webinar (registration is mandatory) please complete the online form:

https://cc.callinfo.com/registration/#/?meeting=1kgd5ce6zz5ae&campaign=1q6ommi9n1dsm

We hope that you will be able to join this online feature from our technical group. The highly successful webinars on the human eye from the past years can still be viewed online at our Technical Group website:

http://www.osa.org/en-us/communities/technical_communities/vc/applications_of_visual_science/.

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Interviewing Jane Weiner: “Losing sight” a documentary about myopia.

The following article is presented to you by Miguel García, Pablo Sanz & Jane Weiner
For all the general public.

Today we have the luck to interview a filmmaker, that has been working during the last years in a documentary on myopia. She had the patience and time to answer to all of our questions.

Jane Weiner
Jane Weiner

Ms. Weiner born in New York. She studied Biology and American History at San Francisco State University, where she graduated in English Literature and majored in Filmic Studies. She also taught communication at the University of Syracuse.

Jane Weiner began as a young filmmaker and nowadays she is well known for her filmographic and audiovisual works. Currently she is making a documentary film related to myopia.

There is no better blog than this to know more about her myopia documentary work!

Go straightforward to the trailer!  Click here!


Good morning, Ms. Weiner!
It is a huge pleasure to see you again. First of all, thank you very much for taking the time to conduct this interview.
I think that there is no better place than the International Myopia Conference to introduce us to your work.

  • Have you been previously in other editions of the IMC? Are you enjoying the experience?

Well, this is my third IMC.  I went first to California, then to China and now, here we are.  I really, really enjoy it!
 At my first IMC, I knew absolutely nothing about myopia, well I can’t say nothing about myopia, because I am myopic, but I knew nothing about eye science. Before my first IMC experience, in fact, I didn’t have time to read anything about the subject, so you can imagine, sitting through those complex lectures was really a challenge, quite a challenge.

But as it happens, I already knew many of people involved in eye science quite well and they were available to answer my questions and guided me through the basic eye science of Myopia. And then over the years, attending both International Myopia Conferences and the ARVOs in United States as well as some other conferences in Europe, I began to really, genuinely understand.  So, for the last 3 or 4 years I’ve had the privilege of studying eye science with the top professors around the world.

  • So, talking about the people…what do you think when you see so many people dedicating their research to the fight against myopia?

Well, my best friend in all the world is Josh Wallman, so I’ve know these people for a very long time, not as scientists but simply as friends, which is a different kind of relationship. Their work is absolutely amazing, but I didn ́t really understand most of it – and, the key to making a movie is that the filmmaker must understand the subject extremely well in order to translate the science into an audio visual experience using everyday language and images that a wide audience of all ages and backgrounds can easily understand.  I’m not working as a journalist — making interviews and editing them together — I’m trying to develop a very clear comprehensible story of what Myopia is and why the current epidemic presents a worldwide public health problem.

  • About the general concern… Do you think that the general public is aware of this problem and its possible causes and consequences in the future?

No, I don’t think the general public knows anything about myopia, in fact in the United States they don’t even use this word. They say ‘near-sighted’ or in England they use ‘short-sighted’.  And, many people don’t have a clue as to why they are wearing glasses.  I’ve heard so many people saying: “Yeah, I’m absolutely near-sighted, I can’t see far” but, when you look at their prescription, it is all plus diopters – so they must be ‘far-sighted’.

So you know, it’s just that people are not well informed by their eye doctors. They go and get an eye exam, get a prescription for eyeglasses and it ́s all magic!

  • Talking about your Myopia documentary…what drew you to telling this story?

My goal is to use images and small stories in conjunction with those images, with the voices of the experts telling the story. We will cover everything from birth to old age, and the main point of the film, although we say it very gently, is that this is a very, very dangerous subject.

  • Maybe with this documentary the general public is more concern about…?

If you say ‘glaucoma’ to the people it’s just a word, they don ́t know what it means. Even from my personal experience, my father had glaucoma and I knew he had to take eye-drops and he could not drive anymore but I didn ́t really know what that meant in terms of reduced vision…

I didn’t understand it at all, until I got it myself, and that’s the same for most people.

  • What was your prior knowledge about myopia?

My prior knowledge of myopia was that almost everyone in my family was myopic:  My father was strongly myopic and he was photographer, architect photographer. I knew that he had retinal detachment and glaucoma but I didn ́t know about its association to myopia.

  • During these years you’ve met some of the greatest researchers in the field, what have you been most surprised to learn about?

I think the most important thing I’ve learned was how serious this subject is and how difficult it is for the scientific and professional community to communicate this to the general public.  There is a real disconnect, even between the scientists and the practitioners and, then, onto the general public. A double disconnection…

  • When you started getting to know what scientists were discovering about myopia, has there been anything that surprised you a lot?

I try to think something that was really the most surprising… I actually do remember, yes… One of the most amazing things for me was that when I began to getting involved in this — I looked first to the Josh Wallman publications, I think the most amazing thing for me was to understand that he had discovered the importance of defocus in the periphery quite early on and that is only recently that contact lenses are being made to ‘manage’ the problem of myopia progression. The scientists weren’t thinking of solving the problem; they were just looking at what was occurring to make an eye myopic.  And we are, right now, at the nexus of where science, discovery, and practical applications come together.

  • Well, yes, there is some slowness to transform into something can be exported to the practice…

Yes, that ́s very slow.  It took many stages, first trying to control peripheral defocus with spectacles, understanding something… then, finding better ways to do it. And, as everything seems to happen in this particular science, discoveries all happen by accident. Those are the great stories!

  • Talking about the documentary…what was the biggest challenge in making the documentary film?

Technically the biggest challenge is that I decided to try to simulate different aspects of vision. Video and film are both two-dimensional while vision is three-dimensional, so that ́s a handicap of making a film. Working in digital you have little bit of room to modify the depth of field and depth of vision but I’m looking into using equipment that is truly three-dimensional in order to obtain a real taste of what is like to see with different eye modalities.

  • With this documentary, are you trying to show what being myopic means for the public?

Oh yes! Absolutely, the purpose for making the documentary is to get the word out about how dangerous any amount of myopia is, particularly in children.  I mean, I have spoken to many, many adults who have never in their life get an eye exam and then they start to have problems, so I say to everyone:  Even if you think you have no problems, go now, get an exam so at least you have a starting point, so that when something else happened you will know at what point you can say, when I was 20 years old, I saw it like this, and when I was 40 I saw like this. So that it gives you some basis for understanding where you are when something goes wrong.

  • Is there any deadline? When will the documentary be released?

I need to rise 500.000 € to make the film properly and I need another one 500.000€, because it’s quite an involved project: 1) a creative feature-length film for cinema distribution, 2) a one-hour TV version – using the same footage, which that is delivered to the public in a more straightforward, basic style, and 3) I’ll also make short little pieces for web distribution or that could be used in eye doctors’ waiting rooms, etc.  Plus using this three-dimensional equipment, we’re creating an educational exhibition for science museums where the people go and discover the different aspects of hyperopia, myopia, astigmatism, and the diseases associated with myopia – glaucoma, detached retina, macular degeneration and cataracts.

From the moment I acquire full funding, I set a deadline of 18 months after so, the time it takes to finish depends on when I am able to obtain the financing. At this point, we’re anticipating the release date to be Autumn 2019.

  • What are you working on next? Is it related to myopia?

It ́s funny, I take a lot of time to make each film. People that I worked with in France told me: “You have 6 weeks to go to Burgundy and film this subject”. And I said: “No, no, no, no…” I spent 3 years living there, meeting the people, and staying on there, filming almost every day…a little bit every day and really gathered an impressive story…so I don ́t really have much headroom left to think what the next project is because when I started this project I thought, “oh no problem, I know all the scientists, it will be very simple, they know what to say and we have a film…!” But first I had to learn a lot, it was like going back to school and then I realized that the project to do in the way that I wanted to do was not a low-budget film.

It turned into a large project, so right now I don ́t really think about what I am doing next, After this is over ideas will come to me but I don ́t have a wish list.

Once again thank you very much for your time. It has been a pleasure to have been able to conduct this interview.  We are really looking forward to watching your project.

All the best!

You are welcome! By the way, I love your blog!


Movie Trailer

LOSING SIGHT – Inside the Myopia Epidemic – a documentary by Jane Weiner.

 Disclaimer, all the rights from the trailer above are hold by the author Jane Weiner. The copy or reproduction in any way is not allowed unless explicit permission from her.

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Ophthalmic Workshop & Complementary Skill Course ’17

The following article is presented to you by Pablo Sanz and Miguel García
For all the general public.

During the last week of June, the MyFUN fellows were at the headquarters of Carl ZEISS Vision International GmbH (Beneficiary 06) in Oberkochen, Aalen.

There, the group received a guided tour through the company, the museum and took part in educational training about OCT, Biometry and Fundus cameras with a hands-on training with these devices.

 

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After 2 great days there, the group moved to Tübingen to have a joint complementary skill course with the Switchboard network. Legal awareness, ethics in biomedical research, intellectual property, properly writing scientific reports or how to keep a lab book were only few of the topics learned during this courses.

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To give an end to that week, some ESRs (Early Stage Researchers) shared their work in front of a more varied group of vision researchers in the Young Vision Research Camp.

 

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Hope you enjoy those pics as much as we do this week!


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A Science Blog curated by Early Stage Researchers of the MYFUN Project