Cornea - Science topic

May consider using Permai fluorescence dye.

the primary functional group of interest in corneal epithelial cells when using FTIR spectroscopy would be amide groups (Amide I and Amide II), which are characteristic of proteins.

First, represent the Zernike polynomial as a complex polynomial in polar coordinates (r, θ) using the Zernike radial polynomials Rl(p) and angular harmonics Pm(θ). Then, evaluate the polynomial at a grid of points on a circular domain (e.g., using a radial and angular resolution). Finally, use the complex values to create a 2D array representing the surface height at each point. You can use libraries like Python's NumPy and SciPy to perform these steps. For example, you can use the `numpy.meshgrid` function to create a grid of (r, θ) values, and then evaluate the Zernike polynomial using NumPy's `polyval` function.

Hi Baffour

What type of microscopy are you using to image your sample?

how thick is your section? Is Beta III tubulin identifying only your cell type of interest?

You should be able to stain with a nuclear marker as well.

You can then segment the image for cell nuclei and subsequently you can analyse those areas - or if your marker is in the cytosol a ring around those objects - in an image of a marker which identifies your cell type of interest. This way you get all the objects, which are poritive for your cell identification marker.

For a few images you can use FiJi (FiJi.sc) for large number of images use CellProfiler (cellprofiler.org).

Best

Heiko

I think you can try something like this

Ji-Yun Kang,

There are a few methods.

1) You can use a vacuum to remove the air between the slides.

2) Take a pair of forceps and very gently push the air bubble to the side.

3) Gently tap the coverslip with your finger from above simultaneously. The bubble moves towards the side of the coverslip and out of the area of the section.

I have found that these work best, also the reagent may be too old and prone to bubbles. Best to use a newer reagent.

Yes, it would be good if you could isolate the lens, since it could break while sectioning, and breaking the rest of the sections.

Mario Rehnert, thank you very much.

That's a good point.

For the ray-tracing, I used the 'front' and 'back related to front' data from the elevation file rather than the pachymetry data. After your comment, I used pachymetry data, which improved my results.

However, there is still a total of 20% difference between the extracted coefficients and the coefficients provided by Pentacam.

Very interesting video Vladimir Siplivy , thanks!

That is right, the iris movement seems predominant. However, we do see tissues being transplanted to the ACE and they all got vascularized. Now, we are aiming to position our device at the angle of the eye where iris movements are minimal.

Olá Flavia,

Fiz uma consulta e vi que o artigo está com a citação correta no ano de 2016. Você pode verificar abaixo. Quais foram os procedimentos que você utilizou para atualizar os dados da citação?

Rocon, P. C., Almeida, A. V. de, & Paro, F. M. (2016). Perfil epidemiológico dos doadores de córneas e doadores de órgãos de cinco hospitais do Estado do Espírito Santo, Brasil. Revista Brasileira De Pesquisa Em Saúde/Brazilian Journal of Health Research, 17(1), 56–64. Recuperado de https://periodicos.ufes.br/rbps/article/view/12450

Muito obrigado por compartilhar,

Jean

A distortion will exist or be expected because of dealing with different projections of the same space. A best fit sphere minimizes the error, therefore what I would do is knowing the orientation of the rectilinear coordinate system, determine the center of the sphere and its xyz offsets and orientation, aligning them in that system. Then at a regular angular intervals of choice to cover the required surface area, determine the spherical coordinates.

I am wondering whether you have experienced such cell loss only on the 96-well plate or also on other flasks or dishes. Anyway, given that your cell line can attach and grow well on the plate but in the absence of the drug, pre-coating the bottom of wells, and spinning down the plate before aspiration may help. If detachment from the bottom is due to drug toxicity, its treatment protocol may need to be modified, e.g., at a longer period of time at a lower concentration.

Other then the conventional statistical approaches for textures analysis , you may also follow https://www.nature.com/articles/s41598-020-67632-z

The bacterium Moraxella bovis (M. bovis) is the main infectious cause of pinkeye in cattle.

M. bovis organism is sensitive to Oxytetracycline and penicillin.

Dear, Brent A Bell Well, I have OCT images of the mouse retina on several instruments including Micron IV, Bioptigen, OcuScience with a few more it can be the foundation for the review. I hope to find few more collaborators to complete the set.

Please follow Dr A K Mandal's (LV Prasad Eye Institute, India) work. He has extensively reported his results of Combined Trabeculotomy with Trabeculectomy in children with PCG, Aniridia, SWS. It works best for children <2 years with cloudy corneas (common presentation in developing nations).

It will depend on your database. You can start with traditional computing, extracting resources, such as filters, lbp, surfing, etc... and if the result is not what you expected, you can try methods that require more processing, such as artificial neural networks and finally deep learning, if you have a robust database and gpu.

use cryosectioning in which the tissue is immersed in cryoprotectant, frozen and then cryosectioned

fresh tissues were immersion-fixed by rapidly replacing the PBS with 10% formalin (Fisher Scientific, Pittsburgh, PA) for 1 minute at room temperature, taken out briefly for imaging and then returned to fixative for 24 hours. To study the effects of sectioning, the 24-hour fixed PPONHs were further processed, including immersing in a 30% sucrose solution for cryoprotection and embedding in Optimal Cutting Temperature compound (Fisher Scientific, Pittsburgh, PA) before freezing in liquid nitrogen (−196 °C). Frozen blocks of PPONH tissue were then cryosectioned coronally at 30 µm thickness (Leica CM3050 S, Leica Biosystems Inc., Buffalo Grove, IL)

If it irritates the eyes then I think it is harmful. It might be better to wear a face shield instead.

Not sure what you are looking for exactly, but you can find some average elevation maps measured with CASIA2 and with Pentacam AXL in the supplementary data of: https://doi.org/10.1371/journal.pone.0223770 .

Hi Nadim, For the cornea we have several options. You would want to look at the use of 1. Boston Keratoprosthesis 2. Alphacor (https://dx.doi.org/10.1038%2Feye.2011.122) 3. KeraKlear 4. Dohlmans Artifical Cornea. For the retina, you can look at : 1. Argus family of retinal implants 2.Nanoretina NR600

The FDA approval is usually via the Humanitarian Device Exemption (https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfhde/hde.cfm?id=H110002)

No indication for an ocular surface condition like phlyctenular keratoconjunctivitis, which is a type-IV (cell-mediated) hypersensitivity reaction to high-MW bacterial (Staph, mycobacteria) capsule proteins. Phyctenular ulceration may occur, but it usually involves the gelatinous proliferative tissue on its apical portion, rather than the corneal epithelium. On the other hand, AC inflammatory reaction is not a common feature of the disease; therefore, ciliary spasm is not frequently present.

I agree with Sebastian. For RNA, just repeat the procedure he mentioned adding trizol to the mortar.

I think it is possible but i don't find research about this technical in cornea, just in retina

Additional Remarks on sprayable after-shaves

1) You may wish to refer to FDA's position on cosmetics

https://www.fda.gov/cosmetics/cosmetics-laws-regulations/fda-authority-over-cosmetics-how-cosmetics-are-not-fda-approved-are-fda-regulated

2) Recently, I looked through the shelves of a well-known retailer in Maryland, USA, for a sprayable after-shave. I wanted to see what warning, if any, was printed on the product. It turned out that there was no sprayable after-shave on their shelves at all. Is this voluntary restraint? Did the manufacturers suspect that such a product could lead to harm to consumers, and to consequential litigation?

you can search your article from google scholars.

I am recommending following article that summarizes the mechanism of CXL: Corneal cross-linking--a review. Meek KM, Hayes S.

If the gold standard assumes a device that is the most prevalent and the one that we can compare the other topographers with, then it is definitely Pentacam, although many other units may be better in one way or another. As mentioned earlier, the future lies in OCT technology, the fanciest of all currently being Anterion by Heidelberg.

You may need to build a model then train with labeled image first to achieve what you need.

The highest we got was 70 ng/dl. I've talked to other researched who have gotten 150 to 600 ng/dl...

Dear Dr Rao

At present we are industrialising a bioreactor dedicated to long term storage of human corneas. By restoring intra ocular pressure (among other things) it allows increasing the viability of endothelial cells (+23% after 4 weeks of storage).

Results will be soon published.

Sincerely yours

Check this link

Hope you good luck

regards

You may try

i- 4% bufferized paraformaldehyde for perfusion.

ii- Increase the perfusion time.

iii- Post fix in 10-40% sucrose gradient solutions and finally freeze it in oct compound.

Thanks!

The most common is infection  ,so as dietary deficient , I think

Why do the corneal endothelial cells do not have an ability to proliferate?

Some thinks it´s important to know.

Human embryo, 7 weeks old.

Human Corneal endothelial cells and keratocytes originate from neural crest cells and then differentiate into mesenchymal cells. Human embryo, 7.5 weeks old: Corneal endothelium consists of a double layer of cuboidal or flat cells. These cells starts to form Descemet membrane.

Human fetus, 5 months old

Corneal endothelium appears as a monolayer at the 18th week. The decrease in cellularity of the endothelium is more rapid during the prenatal months than during the first 2 postnatal years. The diameter of the cornea increase from 4.2 to 9.3mm, from 16 weeks gestational age to term. During this time de endothelial surface increases from 14 to 68 mm². This rapid enlargment provides much more space to be covered by the endothelial cells.The decrese in cellularity and the increase in the surface of the corneal endotelium to be covered cause changes in the packing, size, thickness and shape of the endothelial cells.

Barishak,YR. Embriology of the Eye and Its Adnexa. 2nd Ed. 2001

After this phase the cell cycle remains blocked, some believe that due to factors inherent to the aqueous humor, but there is still no clear proof of the real reason.

It is known that its mitosis after birth is rare. The amount of your cells gradually decreases during life. This major decrease occurs in the first 5 to 6 years of life due to corneal growth in diameter. I suggest you study well the cycle of cell division and expand literature review included the article below.

Okumura N, Inoue R, Okazaki Y, Nakano S, Nakagawa H, Kinoshita S, Koizumi N. Effect of the Rho Kinase Inhibitor Y-27632 on Corneal Endothelial Wound Healing. Invest Ophthalmol Vis Sci. 2015 Sep;56(10):6067-74.

 

Abib FC1, Barreto Junior J. Behavior of corneal endothelial density over a lifetime. J Cataract Refract Surg. 2001 Oct;27(10):1574-8.

It is rare to prove clinically significant mitosis. It is believed that they may be related to herpex virus infiltration. In my professional and research experience I have 2 or 3 well documented cases. If you study endothelium by means of specular microscopy, follow the articles below.

Bernard E. McCarey, Henry F. Edelhauser, Michael J. Lynn. Review of Corneal Endothelial Specular Microscopy for FDA Clinical Trials of Refractive Procedures, Surgical Devices and New Intraocular Drugs and Solutions. Cornea. 2008 Jan; 27(1): 1–16.

Abib FC, Holzchuh R, Schaefer A, Godois R. The Endothelial Sample Size Analysis in

Corneal Specular Microscopy Clinical Examinations. Cornea 2012;31:546–550.

Abib FC, Andrade Neto JL, Abib DS. The sampling error from specular microscopy

examinations and their reliability indexes. Cornea 2013;32:377–378.

Arkadily,  This is an Offner mirror system known as aberration free in terms of spherical aberration, coma and distortion.  But there still remains astigmatism as shown in wavefront analysis of Offner mirror in my attachment.  Regards,  Shigeo

Julio,

About 60 years ago, mixed-effects models were developed (e.g. see Wikipedia).  That approach allows the inclusion of data from both eyes of a subject with the relationship dealt with appropriately when the "clustering" is declared (e.g. error terms, DoF).  Note that there is value in having data from two eyes, in that the high correlation (in healthy eyes) provides a better estimate than data from only one eye.  Such models can also account for other relationships (clusters) such as between siblings and repeated measures over space or time.  Most statistical packages include mixed-effects models (there are a variety of other names for the same thing).

Russell

For an excellent review see: Douglas, R. H., & Marshall, N. J. A review of vertebrate and invertebrate ocular filters. In Adaptive mechanisms in the ecology of vision (pp. 95-162). Springer Netherlands, 1999

The amount of short wavelength transmission by the ocular media depends on the normal light absorption below 310 nm by nucleic acids and proteins of the cornea and lens as well as other short wavelength pigments found (typically in the lens).  Birds and other vertebrates (some fish and reptiles) with UV receptors usually are lacking some of these lenticular short wavelength filtering pigments, thus transmission in the UVA is solely dependent on the path length of  typical nucleic acid/protein absorption. See e.g.

Muntz, WRA. Inert absorbing and reflecting pigments. In HJ A Dartnall (ed.), Handbook of sensory physiology, VII71 Photochemistry of vision,  530-565. Springer-Verlag, Berlin, 1972

Bowmaker, J  Visual pigments, oil droplets and photoreceptors. In P  Gouras (ed.), The perception of colour,  108-127. CRC Press, Boca Raton, Florida, 1991

Finally, primates have an additional short wavelength filter (the macular pigment)  found near the fovea that further reduces short wavelengths from reaching the retina.  See e.g.  Snodderly, D. M., Brown, P. K., Delori, F. C., & Auran, J. D. (1984). The macular pigment. I. Absorbance spectra, localization, and discrimination from other yellow pigments in primate retinas. Investigative Ophthalmology & Visual Science, 25(6), 660-673, 1984.

Thank you Mr. Martin. I have not got any sunburns or any sorts of issues with my skin. The problem is skin cancer symptoms would not be seen until 6-8 months after exposure. So, I am worried on the same.

Dear Piraya,

Hypothermic storage at 2–8 °C is perhaps the most widely applied method world-wide; for example, all eye banks in North America use hypothermic storage owing to its perceived simplicity and its effectiveness. On the other hand, the majority of European eye banks use organ culture at 28–37 °C for storing corneas because of the extended storage time compared with hypothermic storage. Non-viable corneal tissue can be stored by freezing, by freeze drying, in glycerol, or in ethanol.

For more on this topic, please read the review article contained in the following link:

Hoping this will be helpful,

Rafik

Thank you so much for this article. I am wondering if I can see macrophage growth in 12 hours time points after corneal injury. I will follow this method and see. 

Thank you so much.

Hi Yi-Chia, I have some experience with oral fibroblasts, one of the strategies that we used was including insuline as growth factor in the medium or maybe increase the % of  FBS.  I hope this helps you in some way.

Contract research organisation

What about these papers:

Preservation of the Corneal Epithelium in Different Corneal Storage Media.

Soni NG, Hoover CK, Da Silva H, Jeng BH.

Cornea. 2015 Nov;34(11):1400-3. doi: 10.1097/ICO.0000000000000601.

Endothelial Cell Viability of Donor Corneas Preserved in Eusol-C Corneal Storage Medium.

Yüksel B, Uzunel UD, Küsbeci T.

Exp Clin Transplant. 2015 Oct 14. doi: 10.6002/ect.2014.0295. [Epub ahead of print]

PMID:

Cornea preservation time study: methods and potential impact on the cornea donor pool in the United States.

Lass JH, Szczotka-Flynn LB, Ayala AR, Benetz BA, Gal RL, Aldave AJ, Corrigan MM, Dunn SP, McCall TL, Pramanik S, Rosenwasser GO, Ross KW, Terry MA, Verdier DD; Writing Committee for the Cornea Preservation Time Study Group.

Cornea. 2015 Jun;34(6):601-8. doi: 10.1097/ICO.0000000000000417.

Anterior corneal buttons from DSAEK donor tissue can be stored in optisol GS for later use in tectonic lamellar patch grafting.

Chu HS, Hsieh MC, Chen YM, Hou YC, Hu FR, Chen WL.

Cornea. 2014 Jun;33(6):555-8. doi: 10.1097/ICO.0000000000000102.

Eye preservation tectonic graft using glycerol-preserved donor cornea.

Lin HC, Ong SJ, Chao AN.

Eye (Lond). 2012 Nov;26(11):1446-50. doi: 10.1038/eye.2012.192. Epub 2012 Sep 14.

Comparison of different methods of glycerol preservation for deep anterior lamellar keratoplasty eligible corneas.

Li J, Shi S, Zhang X, Ni S, Wang Y, Curcio CA, Chen W.

Invest Ophthalmol Vis Sci. 2012 Aug 17;53(9):5675-85. doi: 10.1167/iovs.12-9936.

Prospective clinical evaluation of McCarey-Kaufman and organ culture cornea preservation media: 14-year follow-up.

Rijneveld WJ, Remeijer L, van Rij G, Beekhuis H, Pels E.

Cornea. 2008 Oct;27(9):996-1000. doi: 10.1097/ICO.0b013e3181783a35.

Influence of temporary hypothermia on corneal endothelial cell density during organ culture preservation.

Schroeter J, Meltendorf C, Ohrloff C, Rieck P.

Graefes Arch Clin Exp Ophthalmol. 2008 Mar;246(3):369-72. Epub 2007 Nov 16.

First report of evaluation of K-M media: a new corneal preservation medium.

Desai BM, Khamar BM, Ghodadra BK.

Indian J Ophthalmol. 2007 Jan-Feb;55(1):43-7.

Optisol vs Dexsol as storage media for preservation of human corneal epithelium.

Greenbaum A, Hasany SM, Rootman D.

Eye (Lond). 2004 May;18(5):519-24.

Improvement of human corneal endothelium in culture after prolonged hypothermic storage.

Camposampiero D, Tiso R, Zanetti E, Ruzza A, Bruni A, Ponzin D.

Eur J Ophthalmol. 2003 Nov-Dec;13(9-10):745-51.

Use of glycerol as an alternative to freeze-drying for long-term preservation of antigen for the direct agglutination test.

el Harith A, el Mutasim M, Mansour D, Fadil Mustafa E, Arvidson H.

Trop Med Int Health. 2003 Nov;8(11):1025-9.

Fibroblast growth factor-2 protects endothelial cells from damage after corneal storage at 4 degrees C.

Rieck PW, von Stockhausen RM, Metzner S, Hartmann C, Courtois Y.

Graefes Arch Clin Exp Ophthalmol. 2003 Sep;241(9):757-64. Epub 2003 Sep 6.

Influence of temperature on corneas stored in culture medium. A comparative study using functional and morphological methods.

Sandboe FD, Medin W, Frøslie KF.

Acta Ophthalmol Scand. 2003 Feb;81(1):54-9.

[Corneal preservation at 31 degrees C--experimental study].

Zemba M, Bobeico V, Bratulescu M, Ciuca C, Popescu M, Musat A.

Oftalmologia. 2003;59(4):54-9. Romanian. 

Comparison of Chen Medium and Optisol-GS for human corneal preservation at 4 degrees C: results of transplantation.

Bourne WM, Nelson LR, Maguire LJ, Baratz KH, Hodge DO.

Cornea. 2001 Oct;20(7):683-6.

Corneal temperature reversal after storage in Chen medium compared with Optisol GS.

Yap C, Wong AM, Naor J, Rootman DS.

Cornea. 2001 Jul;20(5):501-4.

In vitro comparison of Chen medium and Optisol-GS medium for human corneal storage.

Nelson LR, Hodge DO, Bourne WM.

Cornea. 2000 Nov;19(6):782-7.

Preservation of donor cornea prevents corneal allograft rejection by inhibiting induction of alloimmunity.

Kamiya K, Hori J, Kagaya F, Usui T, Amano S, Oshika T, Mizouchi T, Tsuru T, Yamagami S.

Exp Eye Res. 2000 Jun;70(6):737-43.

A morphometric study of endothelial cells of human corneas stored in MK media and warmed at 37 degrees C.

Rootman DS, Hasany SM, Basu PK.

Br J Ophthalmol. 1988 Jul;72(7):545-9.

Please take a look on the following

Title: The Rabbit in Eye Research,

Author: Compiled and Edited by Jack H. Prince.

Publisher: Springfield, Ill., C.C. Thomas (1964)

You can also look on Kirk N Gelatt's book "Veterinary Ophthalmology" 

Contact Dr. Vickery Trinkaus-Randall at Boston University School of Medicine. She has pioneered this, along with her mentor Dr. Ilene Gipson who has retired..

I would do both if feasible. If nothing else, it shows the lengths you are prepared to go to find your answer. 

Below is a link to the video for the flat mounting.

Hello,

İf you want to see all the layers of cornea, that is epithelium, bowman, stroma, descemet and endothelium, than you have to cut perpendicular to corneal surface. In such a section you will have approximately 50 micron of epithelium, 450 micron of stroma, and 20 micron of endothelium.

If you cut parallel to front surface of eye, then you will have epithelium in first sections, then a large stromal surface is obtained, and lastly you may catch endothelium in last sections. This is good if you want to study on corneal stroma, but epithelium and endothelium orientation will be difficult.

Hi Jeremy, 

I teach histological techniques and research the cornea.

It would help to know a bit more about what your research question is, but if looking to study to chick corneal structure, then my advice would be as follows.

1. Fix for 1-2 hours in neutral buffered formalin (e.g. 3.7% formaldehyde in phosphate buffered saline. This may also be referred to as "10% formalin". Just make sure that buffered around neutral pH).

2. Process into paraffin using a short cycle of around 4 hours in total.

3. Cut 3 micron thick sections (using microtome) and mount on charged/coated slides (will help with adhesion). 

4. Bake sections onto slides in 60 degree drying oven for 45-60 minutes.

5. Deparaffinise slides in two changes of fresh xylene, then rehydrate through graded alcohols, followed by water.

6. Stain sections with hematoxylin and eosin (let me know if you need a protocol).

7. Dehydrate slides back through alcohols, clear in xylene, and attach coverslip using plastic mounting medium. 

I regularly use this technique for both human and animal corneas with good results. 

good luck.

Damien

You should give a look at this book. Perhaps it will help you.

For an adult rabbit, 5 kg or greater, you want a silicone hydrogel lens, such as O2 OPTIX from Alcon.  Most likely need 8.4 - 8.6 mm diameter.  A thicker lens such as a -3.0 OD lens should stay in the eye better.  The nictitating membrane should not be a problem.  Years ago we used to excise the nictitating membrane but risk developing an infection.  Also, the lens should be fairly flat.

Would completely agree with Drs. Aquavella and Robaei

The findings are mixed:  some studies have reported no gender effects on corneal biomechanics (e.g. Iyamu E, Osuobeni E. Age, gender, corneal diameter, corneal curvature and central corneal thickness in Nigerians with normal intra ocular pressure. Journal of Optometry. 2012;5(2):87-97.

While other have found significant gender differences: e.g. Strobbe E, Cellini M, Barbaresi U, Campos EC. Influence of age and gender on corneal biomechanical properties in a healthy Italian population. Cornea. 2014 ;33(9):968-72 found men demonstrated greater corneal hysteresis and corneal resistance factor than women did

While another study reported the opposite effect with women having greater corneal hysteresis and corneal resistance factor.  Allam RS, Khalil NM. Evaluation of sex differences in corneal hysteresis. Eur J Ophthalmol. 2015 Feb 7:0. doi: 10.5301/ejo.5000572. [Epub ahead of print]

This is not a simple diffusion of water in one phase. This involves a phase transformation as well. Based on the gas flow rate around the cornea you can select different models. This paper (although in a totally different context) gives you an idea to start:

Thank you for all suggestions. An OCT image is very useful in transparent cornea/ lens/ vitreous cases. The " hi speed" OCT system in the surgical microscope will be necessary equipment for good result. Micro optical probes seem to be good exploring tool below the opaque barrier. Adaptive optics with subtraction techniques in ocular surgery is verily a challenge. If a (doubled) optical hardware connected with software capable to make corrected images fast enough showing " live video", it could be very interesting solution.

in my opinion the best method to isolate RNA from cornea is the RNeasy Plus Micro kit of Qiagen. The amounts of RNA from cornea are always lower than in others tissues. It is very important introduce the cornea tissue after the DSAEK surgery in RNA protect buffer to protect the RNA and avoid his degradation

You have presented an interesting case of an adult male with a history of poor vision OD since childhood, a sensory exotropia, healthy nerves and vessels, and a unilateral pigmentary retinopathy. Most likely this is due to old infection, but other possibilities include an old foreign body with siderosis, inflammatory causes such as Harada's disease or AZOOR, old retinal vascular occlusive events or perhaps an atypical presentation of a bilateral process such as retinitis pigmentosa or vitamin A deficiency. Likely infectious causes are onchocerciasis, diffuse unilateral subacute neuroretinitis, syphilis, ophthalmomyiasis, toxoplasmosis, or rubella. As he is from Africa, there are probably several more infectious diseases that may cause a pigmentary retinopathy that I am unfamiliar with. Perhaps someone with expertise in tropical medicine could add to my list. I recommend a careful history, consider a plain-film x-ray if there is a chance of a retained foreign body, then a laboratory work-up for the most likely infectious diseases. If that does not lead to a diagnosis then I would consider electrophysiology studies to rule out unilateral retinitis pigmentosa, but this is unlikely. There are many good papers on the differential diagnosis of unilateral pigmentary retinopathy. Here is one:

Silveira C, Belfort R Jr, Nussenblatt R, Farah M, Takahashi W, Imamura P, Burnier M Jr. Unilateral pigmentary retinopathy associated with ocular toxoplasmosis. Am J Ophthalmol. 1989 Jun 15;107(6):682-4.

Thank you again for presenting an interesting case. Please let us know what you find.

You can make frozen sections mount them frozen on precoated slides. Keep them frozenadd 3% paraformaldehyde solution on the slides while defreezing them. They should fixe immeadiately.

I use a well standardized method for in situ with formalin fixed tissue. There are a lot of protocols in literature. Of course you need to unmask the dna from linked protein and forming bridges with Proteinase k ( from loweest to highest concentrations, depending on different factors), but is works!No doubts! But this is the reason for using superfrost slices, as Virginie sayd.

Dear Shumoos Taha Hammadi,

If you want to get any serious reply or help with your matter I suggest you attach at least a .jpg or .bmp out of your recent analysis/analyses to this thread.

It makes no sense to discuss anything about not knowing what your problem really is (specimen: ok: we know about EYE (animal-human?) / Cornea epithelium.... but nothing about methods to get sections(?): paraffin-, cryo-, semithin plastic /resin sections, stain(s) used, method of image acquisition etc, etc.).

Sorry to bother you with my request,  but hopefully you'll answer some of my questions.

Be very careful when taking the eyes out. Sometimes just a little too much pressure and the retina will detach and no matter what you do after it is too late.

Thanks Dear

I have looked again at several cross sectional diagrams of the brainstem at the level of the Oculomotror Nuclear Complex and I don't see how a focal lesion at this level would give ipsilateral corneal anesthesia.  Where are the Neuro-ophthalmologists members of researchgate who should be commenting on this?

I would not bother dissecting the cornea at all since the mouse eye is so small.  Just pull out the entire eye.  If you are just looking at macrophages, pull the eye, embed fresh in OCT orienting to give a nice cross section through cornea, make frozen sections (16-20 microns), fix in acetone methanol then stain with a robust macrophage cell surface marker and view on a confocal microscope.  Morphology may not be 100% perfect, but it will be pretty good due to the section thickness, certainly pub quality.... 

Contact Simon Kilvington at University of Leicester who uses and stores our large collection email: sk46@le.ac.uk

Best wishes

F4/80 is an excellent marker for all macrophages. Mannose receptor CD206 should be increased in M2, and CD68 gives good staining, although not be specific for M1. Consider MHC class II for M1.

Isolation of proteoglycans is a multistep complex process. I isolated the PG of palmar fascia. If you want, I will send you the materials and methods section of my dissertation. unfortunately it is Polish.

Sure there is:

Michael Mrochen published something on that, but also Antonio Guirao, or Damien Gatinel and independently myself.

You can read from my publications These:

de Ortueta D, Arba Mosquera S. Mathematical properties of asphericity: a method to calculate with asphericities. J Refract Surg; 2008; 24: 119-121

Arbelaez MC, Vidal C, Arba Mosquera S. Clinical outcomes of corneal wavefront customized ablation strategies with SCHWIND CAM in LASIK treatments. Ophthalmic Physiol Opt;. 2009; 29: 487-496

Arba Mosquera S, de Ortueta D. Analysis of optimized profiles for ‘aberration-free’ refractive surgery. Ophthalmic Physiol Opt;. 2009; 29: 535-548

Arba-Mosquera S, Merayo-Lloves J, de Ortueta D.  Asphericity analysis using corneal wavefront and topographic meridional fits.  Journal of biomedical optics 2010;15(2):028003

Arba Mosquera S, de Ortueta D.  Correlation Among Ocular Spherical Aberration, Corneal Spherical Aberration, and Corneal Asphericity Before and After LASIK for Myopic Astigmatism with the SCHWIND Amaris Platform.  J Refract Surg. 2011 Jun;27(6):434-43

anyway the Equations you are asking for are:

Thank you. I will take a look.

My email is laurence.sullivan@gmail.com

The answer from the bio-mechanics finite element modeling group will include the following aspects:

1) Material is non-linear - in the direction of Mooney–Rivlin, Neo-Hookean or Ogden Material. The simplest case is non-compressible Mooney-Rivlin which requires only one constant. (many references from Ogden)

2) FE Model should include large strains possibility for the shell finite element model.

3) Known models with 1) and 2) are showing good correlations with biomechanical experiments - for validation of material parameters, however, it is better to use the standard 1D tension test - only a fiber. And then to validate the shell model of the real structure (in your case bovine cornea). The final shape of the deflection curve is without any doubts nonlinear.

If you have access to one, it may be helpful to get an aberrometry examination. You can divide the straylight parameters into the corneal and total internal eye parameters and that may help you divide the corneal optical effect from the cataract effect. It's not without problems and the corneal elements are predominantly from the curvature rather than the dystrophic proportion but if you see a major lens effect that may help you inform your patients and assist decision making.

-> the very first entry may be the one you are looking for.

or

May I know how your interest in this question is motivated?

in the case of these patients, A-scan ultrasound biometry should be avoid, the biometry always be done with LASER (double pass technique).

In my opinion for Fungal keratitis the patient will receive topically clotrimazole (1%)- crem twice a day , fluconazole (1%) dros 3 times a day, besides Betadine 2.5% also has antifungal activity. The latest study revealed that fluconazol is better that voriconazole , which earlier was presentes as a very active topical antifungal.

Oral: fluconazole 150-mg/day only 7 days. Good luck !

I agree with Andrea Leonardi ,when fungal infection is suspected and smear and culture are negative for fungus repeat scraping or even biopsy is necessary to identify fungal material .I am not agree for aqueous humor culture because usually hypopyon is steril.

for treatment i use Natamycin 5% or Amphotericin B and Voriconazol when it doesn't respond to traditional treatment .

You must think to necrotizing Herpetic interstitial keratitis too.

Hi Dirk,

The reliability of calculated values is always questionable because of the nonlinearity and anisotropy of corneas behavior. Cornea may not be calculated as a bulk material. To my knowledge the interaction between the layers of the corneal structure has not been calculated satisfactory in general but only for specific stress cases so far. Thats why you find many contradictory values in the literature.

Best Hartmut

Dear Eberhard Spoeri

We can separate the layer readily. We have recently sent six samples to a colleague to test for structure via x-ray diffraction. We should be able to send you samples if your can consider testing stress strain, tensile strength etc. Logistics can be worked out.

Best wishes and many thanks for your response. Much appreciated.

With regards

Harminder

No filters!!! blue one is to activate fluorescein to obtain green highlight of surrounding applanation cone! Without flourescein blue filter does not excitate nothing and Green filters reduce the light. If you do not use fluorescein you have to pay attention to the border of the cone to obtain same picture as fluorescein.