UGR scientists provide early diagnosis of eye disorders through optical technique

Researchers from the University of Granada have provided an early diagnosis of certain ocular diseases that are very common today, such as age-related macular degeneration and keratitis, by applying an existing optical technique that, nevertheless, had never before been used for this purpose.

Scientists from the UGR have studied the image quality in subjects affected by one of these two pathologies, finding a greater amount of ocular aberrations and a higher level of scattering (term associated with the dispersion that light suffers when passing through the various ocular media) in affected eyes compared with results in healthy eyes. This significantly affects visual performance.

This work has been performed by the researcher Carolina Herrera Ortiz, from the Optics Department at the University of Granada, and directed by professors Jos- Ram-n Jim-nez Cuesta and Francisco P-rez Oc-n.

Age-related macular degeneration (ARMD) is the leading cause of central vision loss in developed countries, and mainly affects people of over 50 years of age. As far as keratitis is concerned, this condition causes inflammation of the cornea and can cause blindness, due to the severe alterations that the corneal surface may suffer.

Optical instruments

To carry out this work, the scientists measured the image quality with two optical instruments and used a psychophysical test for assessing visual performance. Results from patients with ARMD were compared with those obtained from a control group of similar age without any ocular pathology. Thus, the researchers could verify that for individuals affected by this condition there is an increased level of ocular scattering that could be mainly due to the disruption suffered by the light reflected in the damaged retina of the ARMD eyes, because a priori optics are not expected to be altered, since it is a retinal pathology.

On the other hand, optical quality and visual performance have also been studied in patients affected by keratitis. Eyes affected by keratitis present a poorer optical quality and a reduced visual performance that improves significantly after the resolution of the pathology. Nevertheless, once medical treatment ends, eyes that suffered from keratitis still have a worse image quality compared to the contralateral healthy eye, a result that significantly influences visual performance even having reached the normal values of visual acuity.

Visual quality characterization

The results of this research carried out at the UGR will make a full and objective characterization of visual quality in patients affected by any of these ocular pathologies. So far, the use of new techniques for assessing objectively the optic quality of the eye has been limited to studies on refractive or cataract surgery. However, as Carolina Ortiz Herrera suggests, this work «may be of particular interest to establish an early diagnosis of certain ocular diseases such as age-related macular degeneration, the main cause of central vision loss in developed countries.»

Furthermore, this technique allows researchers to carry out a monitoring of possible stages of both diseases. Ortiz Herrera stresses the importance of including «both in the clinical practice of optometry and ophthalmology» the use of new techniques that, objectively, could indicate deterioration in vision even when the visual acuity values are normal, since «vision is not only seeing well, but providing quality and comfort.»
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\’Suicide gene E\’ reduces potent drug dosage in cancer patients

Researchers at the University of Granada have found a suicide gene, called \’gene E\’, which leads to the death of tumour cells derived from breast, lung and colon cancer, and prevents their growth. The importance of this new gene is that its use to fight cancer can reduce the potent drugs that are currently used, so that could mean more effective treatment for cancer.

This research was conducted by Ana Rosa Rama Ballesteros, from the Department of Anatomy and Human Embryology at the University of Granada, and directed by professors Antonia Ar-nega Jimenez, Jos- Carlos Prados Salazar and Consolaci-n Melguizo Alonso. Its aim was to study the possibility of reducing the dosage of drugs currently administered to cancer patients using combination therapy with suicide gene E.

Scientists from the UGR have shown that the bacteriophage phiX174 killer gene called E, can be used to induce death in tumour cells. So far, attempts to use many chemotherapeutic (cytotoxic) agents similar to the E gene have shown severe limitations resulting from their toxicity and their poor affinity with the tumour.

Advantages of gene therapy

As Ana Rosa Rama explains, chemotherapy, radiotherapy and surgery show at present «limited» results in advanced stages of cancer. «That is why it is urgent to find new therapies, and gene therapy has emerged as a potentially powerful therapeutic platform.» Her work has shown that «it is possible to use gene therapy as an aid to chemotherapy, improving its results when it comes to attacking cancer, thus allowing the dosage of agents to be reduced and contributing to a reduction in side effects for the patient.»

In order to understand how the E gene works, the researchers conducted studies using various techniques. The results indicate that the E gene\’s mechanism of action is to induce apoptosis (cell death), possibly through mitochondrial injury.

Therefore, they stress that «this new E gene appears as an ideal candidate to be transfected into tumour cells in order to induce apoptosis, possibly through mitochondrial activation, and to increase the sensitivity of these cells to the action of the drug developed specifically to act on them.»

The results of this research suggest the possibility of reducing the concentration of chemotherapeutic agents in current use with cancer patients. Thus, in lung cancer cell line A-549, scientists from the UGR achieved a 14% inhibition of tumour growth and reduced by 100 times the dose of Paclitaxel agent when it was combined with gene E. In the case of colon cancer, the results were similar. However, the most relevant fact was found in the breast cancer cell line MCF-7, in which the dose of the chemotherapeutic agent, doxorubicin, was reduced by 100 times, reaching up to a 21% greater inhibition of tumour proliferation when combined with gene E. Currently, researchers from the UGR are in the process of obtaining a patent for gene E.
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