HIV testing:

Unfaithful spouses, leading cause of HIV infections - Dr. Chandrika Wickramasuriya

By Nilma DOLE

Even though Sri Lanka is a low prevalence country when it comes to AIDS, preventive and remedial steps need be taken to ensure that people realise the consequences of this deadly disease. "While many of the educated people know that one can contract AIDS through risky behaviour, people are still not paying heed to the warnings", said Dr. Chandrika Wickramasuriya, President of the College of Venereologist and Consultant Venereologist at the National STD and Aids Control Program (NSACP), said.

She said that people don't even know where you can get an HIV test done, though people have been advised about AIDS awareness. NSACP is located at 12, De Saram Place, Colombo 10, which is a discreet building made purposely for confidential reasons. People can have the HIV test done free of charge. "In fact, we are better than private institutions where there is HIV testing, because our doctors have a one-to-one discussion with individuals to pinpoint how they got it and possibly help others who would have passed it to them or who may have been infected.

Since the majority of the population are enrolled in school and usually sit for the OL, it is important to give a solid foundation to them to face challenges and threats society.

"In other parts of the island, there are many international and national schools which are also participating in the AIDS awareness campaigns but it is up to parents to permit children to learn how they can protect themselves.

"There are many who don't even go to do an HIV test fearing discrimination if they are positive and in the end infect others. Further, you can't really determine if a person is HIV positive or not because there is a window period where a patient has to be counselled and asked when exactly they suspected they were infected to the time they could have passed it onto others," noted Dr. Wickramasuriya.

The Immediate Past President of the College of Venereologist, Dr. Nimalee Punchihewa said, "Even the most educated people know that indulging in risky behaviour can bring trouble, but they don't heed advice. "She commented that every possible information is available online at www.aidscontrol.gov.lk so there can be no possibility that a person does not know anything. Any information from how to use to a condom to even how people can protect themselves from AIDS is available not only on the website but also our doctors can be consulted for advice" said Dr. Punchihewa.

Nowadays, several factors in society play a big role in influencing the sexual decisions of people. "The internet and various types of media have made people more susceptible, hence it is important to continually educate people", she said.

The clinic conducts free HIV screening tests supervised by six specialists with a professional team of 30 doctors and a total of 110 staff working for the NSACP.

From the moment you enter to the day of the final result, your confidentiality is guaranteed because every patient is assigned a number and not called by the name. A majority of the main hospitals and base Hospitals around the island have free HIV tests and the National Blood Bank screens blood before giving the recipient to prevent the spread of AIDS.

"We have to emphasise that as much as Sri Lanka is a low prevalence country for AIDS, the high-risk group has to be educated, this include MSMs or Men who have Sex with Men and sex with sex workers", stated the doctor.

"If you have the virus, it won't be seen in a test but you can infect others which is how some married women get it from their unfaithful husbands," said the doctor. This is how pregnant women also transmit HIV to the child. There are AIDs patients who live normal lives but it depends on the level of immunity. "While some patients are affected by a little germ others can live without problems provided they take medication and don't infect others," said Dr. Wickramasuriya.

The possible spread of AIDS is the vicious cycle between one high-risk group to another.

Often, it takes anything from six months to 10 years for HIV positive victims to develop AIDS since it depends on their immune system. It has been researched that you can easily live with an HIV positive person using precautions so that you won't contract AIDS. Dr. Wickramasuriya said, "Sri Lanka has a better life expectancy for AIDS patients because most of the anti-retroviral drugs are free whereas in even developing countries, it is expenstive.

From the time Sri Lanka detected its first HIV positive person in 1985, about 1,160 cases have been reported ever since. About 301 developed AIDS in which 201 have died and the rest are leading normal lives.

On the gender incidence of HIV positive cases, compared to statistics before, 20 percent of women were affected with the virus whereas now, 42 percent reported cases have surfaced. The percentage for men is 55 percent and the trend is now increasing in women rather than men since they often get it from unfaithful husbands. At the moment, 65 percent of AIDS victims in Sri Lanka are from the Western Province and the rest of the percentage is scattered islandwide. If we don't open up and speak about topics about sex, drugs and homosexuality, we will not be able to control the spread of AIDS and HIV in Sri Lanka. "Anyone who suspects they got HIV should get the free HIV test done as soon as possible," said Dr. Wickramasuriya.

Mother's body size predicts heart disease in men

Researchers investigating the foetal origins of chronic disease have discovered that combinations of a mother's body size and the shape and size of her baby's placenta can predict heart disease in men in later life.

The research is published in the European Heart Journal.

Professor David Barker and colleagues studied 6975 men born in Helsinki (Finland) between 1934-1944 - a time when not only was the babies' size at birth recorded but also the size of the placental surface.

Other available information included details of the mothers' height and weight in late pregnancy, age, parity, and date of last menstrual period.

They found that there were three combinations of mother's body size and placental shape and size that predicted coronary heart disease in boys when they reached late adulthood (from about aged 40 onwards):

1. An oval-shaped placental surface in short mothers who had not been pregnant before - the narrower the placental surface in relation to its length, the more the risk of heart disease rose, increasing by 14% for each centimetre increase in the difference between the length and breadth of the surface.

2. A small placental surface in tall, heavy women (those with a body mass index (BMI) over 26 kg/m2, the middle value for the women in the study); in these men their risk of heart disease rose by a quarter (25%) per 40cm2 decrease in the surface area.

3. A large placental weight in relation to birthweight in babies born to tall mothers with a BMI below 26 kg/m2; these men had a seven percent increased risk for every one percent larger ratio of placental weight to birthweight.

The associations were independent of the social class of the men or the family into which they were born.

Prof. Barker, who is Professor of Clinical Epidemiology at the University of Southampton (UK) and Professor in Cardiovascular Medicine at Oregon Health and Science University (USA), has already discovered that there is a link between placental weight and heart disease in later life, but placental weight does not indicate the size of the surface that is available for absorbing and delivering nutrients for the growing baby.

"Due to the fact that the shape and size as well as the weight of the placenta were routinely measured at the birth of this group of men, we have been able to show for the first time that a combination of the mother's body size and the shape and size of the placental surface predicts later heart disease," he said.

For each of the three combinations, the babies that developed heart disease in later life tended to be thinner than average, which indicated that they were undernourished at birth.

Prof. Barker said that he thought the explanation for the first combination (oval placental surface in women who have not been pregnant before) is that "an oval placental surface is an indication that the implantation of the placenta was disrupted in early pregnancy, leading to foetal under-nutrition, which, in turn, programmes coronary heart disease in later life". The mechanisms that may play a role in disrupting the implantation of the placenta are not yet fully understood.

For the second combination (small placental surface in tall, heavy women), Prof Barker said: "Although the mother is tall and has a BMI of over 26 kg/m2, indicating that she was well-nourished at the time of her pregnancy, placental growth depends on the structure and function of the mother's uterine wall, which is established during her own foetal life. Therefore, her own foetal experience necessarily affects placentation in her offspring. Foetal growth depends on the availability of nutrients.

Restricted placental growth may, paradoxically, have a greater effect in babies who are growing rapidly because their mothers are well-nourished.

We think that these babies were able to grow rapidly at first, but the small placenta started to restrict their growth mid-gestation, so that by the time they were born, they were under-nourished."

For the third combination (large placental weight in relation to birthweight in babies born to tall women below the average weight), Prof Barker believes the explanation lies in what the mother ate during pregnancy.

"Tallness indicates good nutrition before pregnancy, but their low body mass index indicates poor nutrition during pregnancy," he said.

Prof. Barker says that this research is further evidence of the long-term effect of foetal development. "Chronic disease is the product of a mother's lifetime nutrition and the early growth of her child.

It is not simply a consequence of poor lifestyles in later life.

Rather it is a result of variations in the normal processes of human development."

Now the researchers plan to study the diets and body characteristics (body size and shape, fat and lean mass) of pregnant women, the growth patterns of their babies before birth using ultrasound, and the placentas of their offspring.

They hope to discover the links between the mother, her baby's placenta and the development of the baby's cardiovascular system in ways that lead to poor liver and vascular function - two of the primary culprits for heart disease in later life.

New antibiotics a step closer with discovery of bacterial protein structure

Scientists have uncovered the structure of the protein complex that assembles the tiny hair-like strands that cover the outside of bacteria. Called pili, these 'hairs' allow bacteria to group together and stick to human cells to cause infection - and are therefore a key target for a new generation of antibiotics.

Published today in Nature, scientists have revealed the structure of a complex protein called FimD that acts as an assembly platform for the pili of cystitis bacteria.

The structure of the FimD protein means scientists can see the process of pili assembly, from individual protein subunits to complete structures, for the first time.

Pili are tiny hair-like strands on the outside of bacteria that help them to link together in groups. In the case of cystitis, pili allow bacteria to attach themselves to the wall of the bladder, leading to bladder cells engulfing the bacterium. Once the bacteria have invaded the bladder cells, they escape traditional antibiotic treatment and lie dormant, making recurrent infections very common.

Scientists believe that antibiotics could be developed that disrupt the FimD protein, and therefore the production line of pili proteins.

The UCL/Birkbeck group, together with collaborators in the USA, have already discovered small molecules able to interfere with pilus biogenesis.

Without their pili, bacteria cannot attach to each other or the host, making infection much less likely.

Professor Gabriel Waksman from the UCL Research Department of Structural and Molecular Biology and the Birkbeck Department of Biological Sciences, who led the research, said: "Cystitis is one of the most common gram negative bacterial infections; it can also be extremely painful and surprisingly hard to treat - especially repeat infections."

"Pili are a prime target for a new breed of antibiotics to target cystitis and other conditions, as without pili bacteria are unable to attach themselves to each other or the walls of human cells, and therefore much less likely to cause serious infections."

Pili protein subunits are made inside bacteria and initially transported through the inner cell wall. Each subunit is then picked up by a 'chaperone' protein which takes it across to a protein in the outer cell wall called the 'usher'.

The usher protein coordinates the ordered assembly of pilus subunits, i.e. the growth of the pili. This research, funded by the Medical Research Council, has isolated and crystallised the usher protein in cystitis bacteria, FimD, while it's bound to the chaperone/subunit combination.The structure of FimD provides insights into pilus biogenesis because it unravels the entire mechanism of subunit polymerization and transport across the outer wall of the bacteria. "Scientists have been working for a number of years to work out how pili are assembled.This is the first view of the transportation and assembly of pili in action," said Professor Waksman.

Source University College London

Stem cells from fat used to repair skull defects

Stem cells derived from abdominal fat-used along with a synthetic bone grafting material-are a potentially valuable new approach to repairing skull defects after brain surgery, according to a study in the June issue of Neurosurgery, official journal of the Congress of Neurological Surgeons. Preliminary results suggest that adipose-derived stem cells (ASCs)-easily developed from a small sample of abdominal fat-are a useful material to fill large skull defects.

The researchers used the ASC technique to restore skull defects in four patients, average age 64 years. All patients had persistent skull defects-averaging about 3 by 2 inches in size-resulting from complications after surgery. Stem cells were prepared from a small sample of fat obtained from the patient's abdomen.

These fat-derived stem cells are an intriguing new source of stem cells for research and treatment purposes. Unlike bone marrow-derived stem cells, ASCs can be obtained in large numbers and easily expanded.

Similar to bone marrow stem cells, ASCs can be induced to develop (differentiate) into many different kinds of cells-including bone-forming (osteogenic) cells.

After developing the stem cells, Dr. Thesleff and colleagues combined them with a synthetic bone grafting material (called betaTCP) to fill the skull defects in the four patients. The results were assessed by computed tomography (CT) scans performed the week after surgery and at three months' and one year's follow-up.

The ASC procedure provided good results in restoring the skull defects with firm new bone. On the follow-up CT scans, the new bone filled in gradually, reaching the density of the neighbouring bone within several months.

Source: Wolters Kluwer Health: Lippincott Williams & Wilkins.

How vitamins and minerals may prevent age-related diseases

Severe deficiency of the vitamins and minerals required for life is relatively uncommon in developed nations, but modest deficiency is very common and often not taken seriously. A new research published online in the FASEB Journal, however, may change this thinking as it examines moderate selenium and vitamin K deficiency to show how damage accumulates over time as a result of vitamin and mineral loss, leading to age-related diseases.

"Understanding how best to define and measure optimum nutrition will make the application of new technologies to allow each person to optimize their own nutrition a much more realistic possibility than it is today." said Joyce C. McCann, a co-author of the study from the Nutrition and Metabolism Center at California. "If the principles of the theory, as demonstrated for vitamin K and selenium, can be generalized to other vitamins and minerals, this may provide the foundation needed."

McCann and colleagues reached their conclusions by compiling and assessing several general types of scientific evidence. They tested whether selenium-dependent proteins that are essential from an evolutionary perspective are more resistant to selenium deficiency than those that are less essential. They discovered a highly sophisticated array of mechanisms at cellular and tissue levels that, when selenium is limited, protect essential selenium-dependent proteins at the expense of those that are nonessential.

They also found that mutations in selenium-dependent proteins that are lost on modest selenium deficiency result in characteristics shared by age-related diseases including cancer, heart disease, and loss of immune or brain function. Results should inform attempts to locate mechanistic linkages between vitamin or mineral deficiencies and age-related diseases by focusing attention on the vitamin and mineral-dependent proteins that are nonessential from an evolutionary perspective. Such mechanistic linkages are likely to present opportunities for treatment.

"This paper should settle any debate about the importance of taking a good, complete, multivitamin every day," said Gerald Weissmann, Editor of the FASEB Journal.

Source: Cody Mooneyhan Federation for Experimental Biology