Glaucoma - easily preventable:

Early detection will save your eyes

By Nilma DOLE

Imagine not being able to see your grandchildren when they play, not being able to see your younger daughter's wedding or not being able to cross the street without help. Our vision is something that we take for granted so if we ever lose it, we realise the value of it. This is why we need to check our eyes at least twice a year to see if we have problems with our vision. No matter how old or young you are, complications can occur at any age or due to any cause. Therefore it is imperative that you check your eyes.

Glaucoma is an easily preventable condition where once you detect it early or else the consequences are tragic if you don't detect it early. It is very important for any person over the age of 40 years to check their eyes because it would mean either losing or keeping your vision.

Around the world, blindness is caused by cataract, Age-Related Macular Degeneration (ARMD), Diabetic Retinopathy and Glaucoma.

Statistics

Dr. P.G. Maheepala, Additional Secretary at the Health Ministry said, "Estimated statistics reveal that 285 million people are visually impaired and out of this number, 39 million people are totally blind." He said that the important thing is that when talking about the 39 million, 90 percent of blindness are prevalent in poor communities in the world where 60 percent is treatable and 20 percent is preventable.

He said, "Of the six WHO (World Health Organisation) world regions, South East Asia and Western Pacific account for 73 percent of moderate to severe visual impairment and 58 percent of blindness."

Global blindness is increasing by 1 to 2 million every year which highlights the recent trend towards a decline in infectious diseases, while chronic non-communicable diseases, which affects both the developed and the developing world, are rising steeply.

"At present, we estimate that 150, 000 people in Sri Lanka are blind and out of this number, 18, 000 people are blind due to refractive errors. About 57, 000 have cataract, 10, 500 have macular degeneration, 6,000 have diabetic retinopathy and 15, 000 suffer from glaucoma," said Dr. Maheepala. He said that there are 400, 000 people in Sri Lanka who have low vision in some way that need some kind of rectification.

The Sri Lankan situation has challenges but the Ministry of Health together with support from the Agency for the Prevention of Blindness (IAPB) have developed a plan to combat blindness with the Vision 2020 'Right to Sight' program.

"Breadwinners who lose their sight are seen as burdens not only to society to family so prevention is important, but if problems occur, prompt treatment, therapy and family support is needed," said the doctor. In many parts of the world, blindness adds to individual, family and community poverty. "Effective interventions are available that can prevent or cure 80 percent of blindness and these interventions are not expensive," he said.

Dr. Maheepala said, "With the assistance of our stakeholders, we aim to reduce avoidable blindness in Sri Lanka through the development of a sustainable and equitable national programme for prevention and control of blindness as a part of national health system."

Making the program a success will save 15, 000 people from blindness which is a US$ 25 million savings in lost productivity.

The present situation with regard to the Vision 2020 program is that there are 14 clinics situated island-wide to help detect and combat low-vision. "Free cataract surgeries have been done, 4,000 custom-made spectacles have been given for poor families, eight clinics have been set up to deal with Diabetic retinopathy, seven eye units and 40 mobile clinics have been set up, primary eye care units in main hospitals have been established and three national programs have been started in the Western, Sabaragamuwa, North Central and Southern provinces.

Consultant eye surgeon, National Eye Hospital, Dr. Muditha Kulathunga explained that glaucoma occurs when the aqueous solution in the eye builds eye pressure and this condition affects the optic nerves. Glaucoma is a disease where the optic nerve is damaged, leading to a gradual and irreversible loss of vision which is often, but not always, associated with increased pressure of the fluid in the eye.

"Usually the aqueous liquid in the eyes evaporate naturally to balance and equalise the pressure in the eye but if it doesn't happen, solution is accumulated causing glaucoma," she said.

According to the doctor, there are two conditions of glaucoma, namely acute angle closure and open angle glaucoma. These can occur as primary, secondary or congenital glaucoma which can trigger blindness. Closed angle glaucoma can affect suddenly and is often painful loss of vision leading the patient to channel an eye doctor immediately before permanent damage occurs. Open angle, chronic glaucoma tends to progress more slowly and the patient may not notice that they have lost vision until the disease has progressed significantly.

In rare cases, glaucoma can be hereditary and those who have family members stricken with glaucoma should at least get their eyes checked.

Patients will sometimes notice gradual loss of peripheral vision and they can develop problems in their photographic eyesight. Sometimes, they will feel as though they can't handle seeing bright light and their cornea becomes white (corneal opacity) said the doctor. Symptoms of angle closure glaucoma includes pain in or around the eye ball, redness, headache, nausea or vomiting and visual disturbances, for example halos around lights and in some cases there are no symptoms.

Vision

"If untreated, there is a gradual progression of optic nerve damage, gradual loss of vision leading to total Blindness," said the doctor. Treatment is usually lifelong but it helps maintain and sustain vision.

"There are Beta blockers, miotics, adrenergic agonists, Carbonic anhydrase inhibitors and prostaglandin analogues which can help treat glaucoma," said Dr. Kulathunga.

There is surgical treatment available in the form of YAG laser peripheral iridotomy, Argon laser trabeculoplasty, trabeculectomy, Deep sclerectomy, Filtration procedures, Tube-shunt procedure and Cyclophotocoagulation. Regular follow-up should be done and surgeries require after-surgery therapy and counselling.

Anyone diagnosed to have glaucoma has to continue the medication given by the doctor.

According to the doctor, medication shouldn't be stopped and should be taken as prescribed by the doctor to sustain vision. "Patients tend to stop using the medication if they don't see a vision improvement but they must realise that treatment preserves and keeps whatever vision they have. If they don't heed doctor's advice, they most certainly will lose their vision," she said.

However, the story in Jaffna seems to be different as even though the Jaffna Teaching hospital is fully-equipped with the latest eye equipment and technologies, there is another problem. Dr. Chandrakumar of the Jaffna Teaching Hospital, the first eye surgeon to be appointed at the Jaffna Teaching Hospital said, "There seems to be a genetic eye disorder that has been surfacing.

We are still researching on this condition and will know soon whether it is deadly or not," he said.

The good news is that more than any hospital in Sri Lanka, the Jaffna Teaching Hospital has all the facilities to combat blindness which is an integral part of the Vision 2020 program.

The poor exploited by growing market for human organs

A Michigan State University anthropologist who spent more than a year infiltrating the black market for human kidneys has published the first in-depth study describing the often horrific experiences of poor people who were victims of organ trafficking.

Monir Moniruzzaman interviewed 33 kidney sellers in his native Bangladesh and found they typically didn't get the money they were promised and were plagued with serious health problems that prevented them from working.

The study, which appears in *Medical Anthropology Quarterly*, and Moniruzzaman's decade-long research in the field describe a growing worldwide market for body parts that include kidneys, parts of livers and even corneas. Moniruzzaman said the people selling their organs are exploited by unethical brokers and recipients who are often Bangladeshi-born foreign nationals living in places such as the United States, Europe and the Middle East. Because organ-selling is illegal, the brokers forge documents indicating the recipient and seller are related and claim the act is a family donation.

Doctors, hospital officials and drug companies turn a blind eye to the illicit act because they profit along with the broker and, of course, the recipient, said Moniruzzaman, who questioned many of the people involved. Most of the 33 Bangladeshi sellers in his study had a kidney removed across the border in India. Generally, the poor seller and the wealthy recipient met at a medical facility and the transplant was performed at that time, he said.

"This is a serious form of exploitation of impoverished people, whose bodily organs become market commodities to prolong the lives of the wealthy few," said Moniruzzaman, assistant professor in the Department of Anthropology and the Center for Ethics and Humanities in the Life Sciences. Moniruzzaman recently delivered his research findings and recommendations on human organ trafficking to both the Tom Lantos Human Rights Commission of the U.S. Congress and the U.S. Senate Committee on Foreign Relations.

His briefing included the experiences of Mehedi Hasan, a 23-year-old rickshaw puller who sold part of his liver to a wealthy recipient in the Bangladesh capital of Dhaka. Like many poor Third World residents, Hasan did not know what a liver was. The broker exploited this fact and told Hasan the sale would make him rich.

The recipient died soon after the transplant. Hasan received only part of the money he was promised and is now too sick to work, walk long distances or even breathe properly. He thinks often of killing himself, Moniruzzaman said.

Organ brokers typically snag the unwitting sellers through deceptive advertisements. One ad, in a Bangladeshi newspaper, falsely promised to reward a kidney seller with a visa to the United States. Moniruzzaman collected more than 1,200 similar newspaper ads for the study. The organ trade is thriving in Bangladesh, a country where 78 percent of residents live on less than $2 a day. The average quoted price of a kidney is 100,000 taka ($1,400) - a figure that has gradually dropped due to an abundant supply from the poor majority, Moniruzzaman said.

One Bangladeshi woman advertised to sell a cornea so she could feed her family, saying she needed only one eye to see. That transplant didn't happen, but Moniruzzaman said there have been cases of corneas being sold.

Moniruzzaman said it's important to note that most sellers do not make "autonomous choices" to sell their organs, but instead are manipulated and coerced. He said the global trade of organs is a fairly recent phenomenon - made possible by advances in medical technology in the past 30 years - that represents a form of gross exploitation unseen in human history.

To combat organ trafficking, he recommends, among other steps: - Global governance. The U.S. Department of State should play an active role in putting pressure on national affairs and foreign governments to acknowledge the problem and insisting on crackdowns on brokers, recipients, doctors and businesspeople involved in the trade.

- Transparency and accountability. The State Department should ensure all medical centers have a transplantation registry and verify the relationship between recipients and donors. - Cadaveric donation. Countries such as Bangladesh that do not have a system in which people can donate organs when they die should implement these systems. The United States should provide aid and encourage cadaveric organ donation through educational institutions, news media and religious centers.

Realistically, organ trafficking will never be eliminated, Moniruzzaman told lawmakers on the Human Rights Commission.

"But with our collaborative efforts," he said, "we can significantly reduce this gross violation of human rights."

- MNT

Improving the effectiveness of chemotherapy

Researchers from the University of Zurich have found a cellular brake that protects cancer cells from chemotherapy - and they demonstrate which medication can be used to render it inoperative. Their study published in the journal Natural Structural and Molecular Biology provides the molecular basis for promising therapeutic advances. Although many cancer drugs have already been in use for decades, their mode of action is still unknown. The new research results now challenge a mechanism of action that was previously proposed for a group of drugs and supported with experiments: the Topoisomerase I-inhibitor Camptothecin (Top1 inhibitor for short) and its derivatives used in chemotherapy, Topotecan and Irinotecan.

Problem: emergency cellular brake restricts effectiveness

For a long time, the toxicity of the top1-inhibitors was attributed to discontinuities in the cancer cells' DNA that inevitably caused breaks in the chromosomes during the duplication of the DNA. The team headed by Professor Massimo Lopes at the University of Zurich's Institute of Molecular Cancer Research has now identified a mechanism with which cancer cells protect themselves against damage caused by Top1 inhibitions: Using electron microscopy, the researchers were able to demonstrate that Top1 inhibitors can cause the replication forks that develop during the duplication of the DNA to be restructured. "Reversed" replication forks, or "chicken-foot" structures as they are also known, are formed. This remodeling of the replication forks provides the cancer cells with the time they need to repair the lesion in the DNA and thus prevent disparately cytotoxic chromosomal breakage.

"Until now, the assumed mechanism of action of Top1 inhibitors was comparable to a train hurtling towards an obstacle without brakes that inevitably ends up derailing," explains Massimo Lopes, commenting on the results. "What we have now discovered is the emergency brake, which the cells activate themselves to protect themselves from the inhibitor." Arnab Ray-Chaudhuri, who made a considerable contribution to the study, draws the following conclusion: "Thanks to the discovery of this mechanism, we now understand why chemotherapy does not always work as expected with these drugs."

The existence of such DNA structures was hypothesised many years ago, but it has only just been confirmed in human cells by Lopes's group. These chicken-foot structures are even surprisingly common with clinically relevant doses of Top1 inhibitors.

Solution: render emergency brake inoperative

The new observations reveal an interesting coincidence: In pulling the emergency brake, a family of enzymes that recently attracted a great deal of interest as a potential target for new cancer therapies is involved in the restructuring: the poly-ADP-ribose polymerases, or PARPS for short. After all, PARP inhibitors increase the sensitivity of cancer cells to different drugs that harm the DNA, including Top1 inhibitors.

The new study reveals why: PARP inhibition hinders the reversal of the replication forks and increases the number of chromosomal breaks caused by Top1 inhibitors.

Massimo Lopes and his team thus provide a clear molecular basis for the clinical observations described and pave the way for promising therapeutic advances.

Massimo Lopes's team is currently investigating whether the same or a similar mechanism is activated by other classes of chemotherapeutics and which cellular factors are involved in this molecular "emergency brake".

The aim is to identify tumors in which this mechanism is not active or inhibit the mechanism pharmacologically to improve the efficacy of chemotherapy.

- MNT