Biology – Australian Science

Exciting New Research Explores a Third Alternative to Infectious Disease Control

Josip — Mon, 28 Dec 2015 06:28:03 +0000

When it comes to infectious disease control, there are two common solutions. These include using medicines, such as antibiotics, to target the pathogens and parasites, or reducing the risk of spread by using preventative measures.

However, a recent collaboration between University of Colorado Cancer Center and University of Virginia led to a discovery that demonstrated the effectiveness of a third alternative. This exciting new research looks at manipulating characteristics of the human body to eliminate the mechanism that permits pathogens to cause the disease.

The findings not only demonstrate how a cancer-science approach can be applied to the field of infectious disease, but it will also have major implications for a disease that causes many thousands of deaths all over the world.

What is Entamoeba Histolytica?

Parasites are organisms that live in or on another organism, known as the host, in order to survive. They gain benefits by deriving nutrients from, or at the expense of the host. While some parasites don’t affect the host organism, others multiply, grow or give off toxins, which can result in a parasitic infection and some very unpleasant symptoms.

There are several ways in which you can contract a parasite, however poor hygienic practices, contaminated food and water, unclean fruits or vegetables and undercooked meat are the most common methods of transmission.

Entamoeba histolytica, or E. histolytica, is a one-celled parasite that kills human cells and causes a disease known as intestinal amebiasis. Amebiasis is a parasitic infection of the intestines, which infects approximately 50 million people worldwide, while causing over 100,000 annual deaths.

According to the Centers for Disease Control and Prevention, only about 10% to 20% from those who are infected with E. histolytica become sick from it. Symptoms tend to be mild and include stomach pain, loose stool and abdominal cramping.

A severe form of amebiasis, known as amebic dysentery, is associated with fever, severe stomach cramping and frequent bloody and watery stools. It occurs if the parasite invades the lining of the intestine and is a much more dangerous form of the disease. If the parasite were to enter your blood stream, it can end up in the lungs, brain, heart, liver, or other organs, and cause abscesses and tissue destruction.

Transmission of E. Histolytica

Entamoeba histolytica is spread by faecal-oral route. While amebiasis can affect anyone, it is more common in those who live in, or have travelled to, tropical countries with underdeveloped sanitary conditions. Areas with high rates of amebic infection include parts of Central and South America, Africa, Mexico and India.

Others at greater risk for amebiasis include people with compromised immune systems and other health conditions, those who live in institutions with poor sanitary conditions and men who have sex with other men.

Current Solutions

Currently, there are two widely used strategies when it comes to protecting humans from infectious disease. These include using medicines such as antibiotics to target the pathogens and parasites, or addressing the environmental factors that permit transmission of the disease.

In the case of E. histolytica, antibiotic is available for treatment. Uncomplicated cases of amebiasis are generally treated with a 1-day course of antibiotics.

However, if the parasite is present in the intestinal tissues, then damage to infected organs must also be addresses. In these cases, surgery may be necessary. Amebiasis can be deadly if left untreated.

Preventative measures to avoid amebiasis focus on proper sanitation. The CDC offers advice on measures to take when traveling to a country with poor sanitary conditions. This includes drinking bottled, boiled or treated water, thoroughly washing fruits and vegetables before eating and avoiding food sold by street vendors, unpasteurized dairy products and ice cubes or water fountains.

Exploring a Third Strategy

New research has demonstrated the effectiveness of a third strategy against infectious diseases. This involves manipulating the host’s genes in order to remove the mechanism that allows pathogens to cause disease.

The collaboration for this research stemmed from a conversation between Dan Theodorescu, MD, PhD, director of the University of Colorado Cancer Center and William A. Petri, Jr., MD, PhD, chief of the Division of Infectious Diseases & International Health at the University of Virginia.

The idea was to apply a groundbreaking technique used in cancer research to the study of infectious disease. Together with Chelsea Marie, PhD, postdoctoral researcher in the Petri Laboratory at Virginia, they sought to determine if the elimination of any one cell could provide immunity to Entamoeba histolytica, through the silencing of genes found in human cells.

This was done by using a technique called RNAi, which allowed them to create a library of bladder cancer cells with thousands of independent, silenced genes. These cultures were then challenged with the E. histolytica parasite.

When this technique is used in cancer research, they look for genes that make cells more susceptible to chemotherapy when silenced. For this research, the infectious pathogen was the analogue of chemotherapy.

While the parasite managed to decimate many thousands of those independent cell structures, a small number appeared to resist it. In order to find out if these silenced genes offered immunity to these cells or merely survived by chance, Marie retested those cells that had survived.

This process was repeated over nine generations of cells, and over these generations of selection, the cultures became more and more enriched for cells that lacked certain genes. The genes that presented resistance were then identified using next generation sequencing.

This revealed that many of those genes were involved in potassium transport, managing the flow of potassium into and out of human cells. A follow-up experiment then revealed that new intestinal cells treated with E. histolytica demonstrated potassium efflux just prior to cell death. That meant that those cells that were unable to transport potassium didn’t die.

The researchers then reversed the direction of their experiments in order to confirm that this was indeed what was causing the resistance to the parasite. They took new cells and blocked their ability to transport potassium, through the use of drugs. By blocking potassium efflux, they were able to manufacture cells that were resistant to the parasite.

The targeting of human genes that enable E. histolytica to cause disease is a major discovery. It demonstrates that cancer-science approach can be applied to the field of infectious disease in order to explore genetic mechanisms of resistance.

Cite this article:
Ivanovic J (2015-12-28 06:28:03). Exciting New Research Explores a Third Alternative to Infectious Disease Control. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/biology/exciting-new-research-explores-a-third-alternative-to-infectious-disease-control/

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How Your Sunscreen Poses a stop Real Threat to Coral Reefs

Josip — Tue, 24 Nov 2015 09:35:24 +0000

Experts advise us to apply sunscreen on a consistent basis. We all know the associated risks of being overexposed to our sun’s rays, yet recent scientific studies have shown that chemicals used in common sunscreen products may also be causing irreparable damage to our planet’s coral reefs.

The media has also started to take notice of the startling warnings. You may have read the sensationalist headlines, with words such as ‘killing’ or ‘destroying’ being used to describe sunscreen’s effect. But in this case, it’s not just clickbait.

While climate change is still the primary cause for concern, the ingredients found in most sunscreen products have now been scientifically proven to cause damage to our coral reefs. We’ve already lost 80% of coral reefs in the Caribbean. If we want to continue enjoying those beautiful holidays in the Great Barrier Reef, something needs to happen.

And no, this isn’t scaremongering or pseudo-science. Two peer reviewed studies have been conducted that put matters beyond reasonable doubt:

Sunscreens Cause Coral Bleaching by Promoting Viral Infections. Published in April 2008, you can read the full study at PMC.
Toxicopathological Effects of the Sunscreen UV Filter, Oxybenzone (Benzophenone-3), on Coral Planulae and Cultured Primary Cells and Its Environmental Contamination in Hawaii and the U.S. Virgin Islands. This recent study from October 2015 has had heavy press coverage recently. The study is heavy reading, so you may want to read the shorter explanation by one of the authors if you want to get a grip on the material.

Of course, the scientific jargon can be a little confusing and that’s understandable. The following explains the core of the issue in slightly simpler terms.

The Problem (In Layman’s Terms!)
The study published in the Archives of Environmental Contamination and Toxicology (October 2015) deals specifically with oxybenzone (benzophenone-3). The study calls the threat from this chemical ‘ecological and existential’. The chemical is described as being ‘highly toxic to juvenile corals’, affecting them in four distinct ways:

Damaged DNA: oxybenzone damages the DNA of juvenile corals, causing them to have trouble reproducing. And even if they do reproduce, the offspring is usually not optimally healthy.
Coral Bleaching: Sunscreens promote viral infections in coral, causing coral bleaching. This is extremely worrying, associated with natural events such as El Nino. Oxybenzone can cause coral to bleach at lower temperatures, posing an even greater threat to the environment.
Endocrine Disruptor: Juvenile coral that has been exposed to oxybenzone can sometimes lead to death due to skeletal encapsulation.
Deformity: Oxybenzone causes deformity in coral, which severely impacts health.

The studies also found issues with other chemicals. Butylparaben, a preservative, has also been linked to coral bleaching. Ethylhexyl methoxycinnamate and 4-methylbenzylidene camphor fall under the same category. Considering just how damaging coral bleaching is, it’s undoubtedly a worrying scenario.

Perhaps the most worrying aspect of the study is that very little of these chemicals are required to cause damage. In fact, it’s as little as one drop of water in what would be the equivalent of almost seven Olympic swimming pools. Considering that it’s estimated that up to 14 thousand tonnes of sunscreen washes of our bodies each year, the potential results are frightening.

And that figure doesn’t even include water and waste discharges. Just think of the sunscreen that we use before going out for a run, enjoying an outdoor barbecue, or catching a few rays while relaxing in our gardens and parks. We all proceed to wash our sunscreen off, potentially landing in our waters and damaging coral reefs.

What Can We Do About It?

It’s clear that the effects of human activities on our environment are worrying, but it’s still possible to protect yourself from the sun’s harmful rays without having an impact on the planet. If you’re going to be swimming, snorkeling or scuba diving near coral reefs, ensure you opt for a coral reef safe sunscreen.

Considering that major brands such as L’Oreal and Coppertone both use oxybenzone, it’s clear that consumers are going to have to do a little digging to find a suitable alternatively. Unfortunately it’s not as easy as looking for a simple label, but there are ways of figuring out which products are safe to use:

The main ingredient you’re looking to avoid is oxybenzone. This is the chemical that has been scientifically proven to harm coral reefs.
Inspect the product label and also avoid butylparaben, octinoxate, and 4-methylbenzylidene camphor. The latter is banned in the USA and Japan, but both Canadian and European sunscreens may contain it.
The problem with sunscreen is that it comes off while in the water. Look for a product that has been proven to be effective at being water resistant, meaning it will stay on your skin (and off our coral reefs!).

It’s worth keeping in mind that a government body does not officially regulate coral reef safe sunscreens. Such labels are simply promotional and set by the manufacturers themselves, meaning that it’s up to you to check the ingredients carefully. If you are in doubt, email or tweet the manufacturer to verify whether the product meets the above requirements.

We can also look to our governments. For example, local authorities in American cities such as Fort Lauderdale and Ocean City have constructed sewer outfalls that divert wastewater from beaches into the ocean. In addition to the problems with sunscreen waste, this toxic mix also contains birth-control pill residue and other harmful products. It’s imperative that we encourage our powers that be to consider the environment and not just convenience or the almighty dollar.

Remember, coral reefs don’t just add to a picturesque setting, an exotic artwork for us to admire. Coral reefs also play an integral role in biodiversity, protect our coasts from natural disasters, encourage tourism around the world, and also have an impact on marine life (having significant value to fisheries). If we’re to continue enjoying these natural wonders, we need to act quickly and decisively.

Cite this article:
Ivanovic J (2015-11-24 09:35:24). How Your Sunscreen Poses a stop Real Threat to Coral Reefs. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/biology/how-your-sunscreen-poses-a-stop-real-threat-to-coral-reefs/

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FDA Approved an Injection That Will Eliminate Your Double Chin

Dunya — Mon, 01 Jun 2015 07:44:01 +0000

For many of us, trying to hide our double chin – perhaps under a scarf or turtleneck – is a daily battle. It’s a major cause of embarrassment for thousands of affected Australians, and is usually caused by obesity or other natural effects of aging. A double chin is actually just an extra layer of submental fat that forms around the neck and can sometimes sag, creating the impression of a second chin. Up until now, surgery was the only way to remove it.

However, there is now a surgery-free way to remove the dreaded double chin thanks to a recently FDA-approved drug called Kybella (or deoxycholic acid). Approved as a treatment for adults with moderate-to-severe submental fat below the chin, Kybella is an injectable drug that works by helping the body absorb fatty tissue. In essence, the drug dissolves the submental fat under the chin by destroying the fat cell’s membrane, causing it to burst. The remains of the cell are then reabsorbed by the body’s normal metabolic pathways.

According to the results of numerous clinical trials, injecting Kybella into the affected area can produce a noticeable reduction in submental fat in just 6 months. Patients can receive up to 50 injections in a single treatment (which usually lasts around 5 minutes), and sessions must be spaced at least 1 month apart for best results. No bandages are required, and recovery time is between 2 and 3 days.

Image source

There are some side-effects, however, that patients need to be made aware of before embarking on this journey. The most common side-effects reported in clinical trials were swelling, bruising, pain, numbness, redness and areas of hardness around the treatment area. However, most of these should disappear within a few days after treatment.

It’s important to understand that Kybella can also cause far more serious side-effects, such as possible nerve damage in the jaw. Although these side-effects are much less common, some patients have reported uneven smiles, weak facial muscles, and even trouble swallowing after receiving treatment. Indeed, according to Amy G. Egan of the FDA’s Center for Drug Evaluation and Research, “Treatment with Kybella should only be provided by a licensed health care professional, and patients should fully understand the risks associated with use of the drug before considering treatment.

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My Dog Speaks To Me With His Eyes – Evolution of Human/Dog Bonds

Lia Paola Zambetti — Mon, 11 May 2015 10:11:21 +0000

Puppy love – same as baby love? Yes, it seems so:

“My dog talks to me with his/her eyes

Cite this article:
Zambetti L (2015-05-11 10:11:21). My Dog Speaks To Me With His Eyes - Evolution of Human/Dog Bonds. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/news/my-dog-speaks-to-me-with-his-eyes-evolution-of-humandog-bonds/

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Life – Evolved

Lia Paola Zambetti — Mon, 24 Nov 2014 00:15:56 +0000

What is a life form? Most of us, if asked, will think of an animal or a human being-in other words, a multicellular organism. However, life itself evolved in cells, single cells of various types that existed and propagated independently. What are, then, the factors that led cells to collaborate together and give rise to complex organisms? Collaboration is possible only if there are no cheaters -cells that exploit the collaboration of others- and cheaters always arise. How is possible, then, for a multicellular organism to develop? Do the cheaters need to be eliminated –an evolutionary impossibility- for complex organisms to occur? This seems the classic common sense response. However, new and unexpected findings by a team of scientists working in New Zealand and the US, suggest the opposite: that the presence of cheaters can be instrumental to the formation of self-generating groups of cells, or collectives.

Evolution can be studied in many ways; fossil examination is a well-known example. However, for researchers looking to have results in a quicker fashion –and with the added bonus of controlling variables within their experiments- bacterial models are the gold standard. Bacteria are used as they grow fast, in most cases multiple generations in one day, and their visible characteristics (their “phenotype

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Multi-Coloured Vision

Lizz Rice — Fri, 15 Aug 2014 00:15:14 +0000

Colour is our eye’s interpretation of light reflecting off objects. The different colours we see are different wavelengths of light. Colour-specific photoreceptors in the retina of our eyes, cones, translate the wavelengths into what we see as colour.

Humans generally have three types of cone to do this. One responds to shorter waves of light (we see these as blues), one responds to longer waves of light (reds) and one responds to the middle lengths (greens). The cones work together to see other colours, such as purple.

The three cone system is called trichromatic vision, but most other mammals, like dogs and cats, only have two types of cones. This is known as dichromatic vision.

Some people only have dichromatic vision too. We call this colour blindness, somewhat misleadingly, as dichromats still have plenty of colours available to them.

Rather, they struggle to make out some colours. They can be defined asprotanopes (total lack of red cones), deuteranopes (lack of green cones) or tritanopes (lack of blue cones).

There is also another group of people called anomalous trichromats, who have all three cones but make odd judgements compared with the rest of us. The peak sensitivity of one of their cones shifts along the spectrum, so they need more or less of the wavelength to achieve the colour. For instance, people with deuteranomaly (the most common) find their green cone sensitivity shifts towards the red part of the spectrum, so they need fewer long waves of light to see red.

It is rare to be born a tritanope, but around 8% of men and 0.5% of womenare affected by red or green colour blindness.

It is so much more common in men because the gene responsible is carried on the X chromosome. Women (XX) are likely to have a normal copy to override the mutated gene, whereas men (XY), with only one X chromosome, have no other choice.

It is also possible to acquire colour vision defects through problems like disease and injury.

The visual world of the colour blind not only becomes less rich, but simple tasks like detecting sunburn, or determining ripe fruit becomes a struggle. Jay Neitz’s slideshow shows what living in a colour blind world might be like.

There are advantages to dichromacy. Researchers have identified 15 shades of khaki that those with normal vision found almost impossible to tell apart, but those with deuteranomaly were able to easily distinguish.

Their ability to discern camouflage may have provided an evolutionary benefit because a reduction in colour signals makes the differences in texture and brightness more apparent. This would explain why it is so prevalent in society.

But they lack the ability to, say, spot a cherry on a cherry tree, which is possibly why we evolved trichromacy in the first place.

Our world has been designed for trichromatics and living with colour deficiency can be detrimental to many areas of life: education, where colour-coding is extensively used, or pursuing careers, for example, as a firefighter, electrician or pilot.

In the future it may be possible to use gene therapy to correct colour blindness. The idea has already been successfully applied to monkeys.

Adult squirrel monkeys (Saimirisciureus) with red-green colour blindness were trained to touch the location of a coloured patch among grey dots. After treatment that added the missing visual pigment gene, the monkeys passed the test with flying colours.

The success of these nervous systems to respond to a new sensory input indicates that, contrary to popular belief, the capacity for development does not end.

It is not known how the human brain would respond to a new colour channel. Though there was no psychological distress observed in monkeys, the internal experience cannot be discerned. Safety also must be ensured before it can be considered for human use.

There may be another way.

Neil Harbisson hears colours. He is the wearer of an “eyeborg

Cite this article:
Rice L (2014-08-15 00:15:14). Multi-Coloured Vision. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/biology/multi-coloured-vision/

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The Health of the Honey Bee

Lizz Rice — Tue, 15 Jul 2014 00:15:33 +0000

The delicate state of the European honeybee (Apismellifera) can be traced back to 2006, when the mysterious Colony Collapse Disorder (CCD) began wiping them out. Adult honey bees went missing from their hives, and no bodies were to be found. Since, apiaries have struggled – the US reports a yearly loss of about 30% – leaving the future of the honey bee in a precarious position.

It is thought the sudden collapse is caused by a number of factors working together in synergy, pounding bee’s immunity so they are no longer as resilient as they used to be.

Exposure to pesticides has been afiercely debated and much publicised culprit. A group of neurotoxicants called neonicotinoids have been found to create an increased susceptibility to gut pathogens in honeybees. They have also been found to affect bee behaviour, learning and memory,crucial for them to forage, find their way home and relate the information to the colony.
Much of this research has been performed in the laboratory, however, and it is questionable how well the findings can be applied outside of it. In this environment, bees exhibit differences in their physiology and stress levels, and studies tend to expose them to an unrealistic level of neonicotinoids.

How much pesticides open the door to other threats is uncertain. Without improved field testing it is difficult to assess the amount of exposure honey bees are actually receiving and their reaction to the combinations and accumulations of pesticide smothered crops.

The EU has frozen the use of neonicotinoids while a more accurate estimate of risks is developed.

Despite not being native to Australia, the honey bee is well established, where feral colonies and hives managed by beekeepers are spread over most of the country.

Neonicotinoids remain in extensive use in Australia. The Australian Pesticides and Veterinary Medicines Authority (APVMA) in 2013 concluded that these pesticides were less of a risk compared with those before.

As beekeepers move away from the chemical-free sources of nectar and pollen found in native scrub and forest and into agricultural and horticultural pollination, there is a commensurate increase in exposure to agricultural chemicals.

This means more rigorous testing of pesticides needs to be done, with improved labelling, regulation and guidance of products used in agriculture.

Changes in land use, where flowering meadows and weeds have given way to agriculturally intense monocultures, mean that bee’s natural foraging habitats are disappearing.

One study has analysed honey bee’s foraging preferences so as to establish which areas would cause them least amount of disruption. Their great foraging range and sensitive response to forage quality means they can be used as bioindicators to monitor large areas and inform environmental management.

Pollen quality and diversity has a major influence on bee’s health and their ability to cope with pathogens, pesticides and parasites such as Varroa destructor.

Varroa destructor is considered to be one of thedriving forces behind colony loss.The lifespan of adult workers in affected broods are reduced,so they cannot survive winter long enough to produce the next generation (Dooremalen etal, 2012).

Varroahas spread all over the world with devastating effect, although whether it attacks immunity or it is the mite’s feeding activity that causes such problems is not yet clear. Of all the major honey producing countries, only Australia remains mite-free.

Australia hosts a large number of feral honey bees due to a warm climate and plants rich in nectar. This high reliance on feral bee pollination means the impact of Varroa could be great, as Australia does not have the resources to offset the effects.

Casey Cooper, president of the New South Wales Apiarist Association, stresses the importance of not letting Varroa get here in the first place.

By increasing biosecurity, pests and diseases like Varroa mite are kept out of the country. Biosecurity includesmeasures such as port surveillance, where hives are kept at all ports and areas and monitored regularly.

Australia is not reporting the huge losses that other countries are. Cooper, however, argues that his organisation has seen a 30% decrease in hives for registered beekeepers since 2006. He believes there is a looming food security crisis related to the decline of honeybees.

Ian Zadow, Chairman of the Australian Honey Bee Industry Council, estimated that “one in three mouthfuls of food we eat relies on the honey bee for pollination of that food.

Cite this article:
Rice L (2014-07-15 00:15:33). The Health of the Honey Bee. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/biology/health-honey-bee/

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The Vaccination Debate: Answers to Common Questions about Vaccination Safety

Dunya — Fri, 27 Jun 2014 10:37:12 +0000

Vaccinations are not mandatory in Australia, yet it is relatively standard for most children to be vaccinated against diseases such as polio, hepatitis and meningitis. However, in recent years questions have been raised about whether the problems outweigh the advantages of vaccinations, sparking intense debate amongst parents, scientists and the general public.

Here, we take a look at some of the most common questions that people ask in regards to vaccination safety.

Can vaccinations cause autism?

For nearly two decades there are myths surrounding the relationship between autism and vaccines. In 1998, respected medical journal The Lancet published a paper that appeared to link the common vaccinations for measles, mumps and rubella (MMR) with autism. This research, by surgeon and medical researcher Andrew Wakefield, resulted in global widespread media attention. However, The Sunday Times newspaper in the United Kingdom later revealed that Wakefield had not disclosed a conflict of interest with a pharmaceutical company that was looking to patent a single measles vaccine. As such, he was taken off the medical registrar and his research detracted.

Several years later, Japanese researchers did their own unbiased research that dispelled the myth that there was a positive correlation between the MMR vaccine and autism. (David Channon, 2014)

What are the risks associated with vaccinations?

Every medical procedure and treatment has an element of risk attached to it, and vaccinations are no different.

The most common side effects of vaccinations are minor, including mild fever, redness and rashes. These will generally subside within a few days. (Immunise, 2014)

However, what has most people concerned are the more serious side effects. While life-threatening side effects are very rare, they do exist. (CDC, 2014) There is no guaranteeing that a person will not react badly to a vaccination, but any bad reactions are highly regulated by the Australian Government. All health practitioners are required to report, in detail, any adverse side effects they witness in a person to the Health Department. With this data, the Department will respond accordingly with the priority of public safety as its focus. (Government of Western Australia, 2014)

Can the body immunise itself without vaccinations?

Many people believe that the body should immunise itself by developing natural immunity to diseases. While the body is fantastic at fighting off many diseases, there are some that it simply isn’t strong enough to control on its own. And, if left to fight off certain diseases it can result in unnecessary serious illness or even death. This is particularly true in those with weakened immune systems such as children and the elderly.

When the body catches a disease such as chicken pox, it fights it off and remembers how it did it. Then, the next time the body contracts the same infectious bacterium, virus or fungus, it knows how to deal with it. Vaccinations are designed to ‘trick’ the body into thinking it has previously contracted a particular disease, without actually giving the person symptoms of the disease. This means that if they were to come into contact with it, the body would recognise it and be able to fight it off. (Better Health, 2014)

Why vaccinate when most diseases have been largely eradicated?

We are fortunate in Australia – as well as other developed countries – that many diseases that once killed tens of thousands of children every year are now incredibly rare. This has led to the misconception that vaccines are no longer required for diseases such as polio and measles. However, the reason that these diseases are so uncommon now is because vaccination rates are so high.

If you would like to read more on this topic, here are some great resources where you can find more information about vaccination safety:

http://www.immunise.health.gov.au/internet/immunise/publishing.nsf/Content/

http://www.cdc.gov/vaccines/vac-gen/6mishome.htm

http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Immunisation…

http://www.travelvaccinationclinic.co.uk/5-common-vaccine-myths/

http://www.health.wa.gov.au/vaccination/#surveillance

http://www.bbc.com/news/uk-wales-politics-23244628

Photos by: Daniel Paquet and NIAID

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Applications of Nanotechnology in Medicine

Milica Djekic — Wed, 05 Feb 2014 00:15:12 +0000

Nanotechnology can be viewed as the science and engineering included in the design, synthesis, characterization, and application of materials and devices whose smallest functional organization is on the nanometer level or one billionth of a meter. At these scales, consideration of individual molecules and interacting groups of molecules becomes important. Applications to medicine imply materials and devices designed to interact with the body at molecular scales with a high degree of specificity.

Introduction

Nanotechnology and nanoengineering appear to produce important scientific and technological advances in diverse fields including medicine and healthcare. Materials and devices engineered at the nanometer scale imply controlled manipulation of individual constituent molecules and atoms in how they are arranged to form the bulk macroscopic substrate. This, in turn, means that nanoengineered substrates can be designed to exhibit very specific and controlled bulk chemical and physical properties as a result of the control over their molecular synthesis and assembly. For applications to medicine and healthcare, these materials and devices can be designed to interact with cells and tissues at a molecular level with a high degree of functional specificity, thus allowing a degree of integration between technology and biological systems. Nanotechnology is not in itself a single emerging scientific discipline but rather a meeting of traditional sciences such as chemistry, physics, materials science, and biology to bring together the required collective expertise needed to develop these novel technologies.

What is a Nanomaterial?

Nanoscience will impact the design and fabrication of new materials with innovative properties and functions. Contributions to this field include improving the properties of plastics, ceramics, coatings, composites, fibres and many more. Nanoscience also introduces an entirely new concept in material design. As a matter of fact, nature is a great source of inspiration to materials engineers.

The question: What is a‘nanostructured material’? must be considered. Nanostructured materials are solids or semi-solids characterized by a nano-sized inner structure. They differ from crystalline, microstructured and amorphous solids because of the scale order. In contrast, microstructured materials show structural variation only on a micron scale, whereas amorphous materials exhibit short-range order only. In nanostructured materials, the spatial order is at the nanoscale, which lies between the microscopic and the atomic scale.

Nanostructured materials differ from conventional polycrystalline materials in the size of the structural units of which they are composed. They can exhibit properties that are drastically different from those of conventional materials. This means that in a nanostructured material there is a large proportion of surface atoms. Due to the large surface area, bulk properties become governed by surface properties. Examples of nanostructured materials are nanoporous, nanocrystalline, nanocomposite and hybrid materials.

Methods in Nanotechnology

Different methods for the synthesis of nanoengineered materials and devices can accommodate precursors from solid, liquid, or gas phases. In general, most synthetic methods can be classified into two main approaches: “top down

Cite this article:
Djekic M (2014-02-05 00:15:12). Applications of Nanotechnology in Medicine. Australian Science. Retrieved: Apr 30, 2024, from http://australianscience.com.au/biology/applications-of-nanotechnology-in-medicine/

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The Future of Fertility Treatment: Advanced Embryo Selection

Dunya — Thu, 21 Nov 2013 00:08:03 +0000

It is incredible just how far science and technology have come over the last few decades. In the past, men and women with fertility problems had very few options. Nowadays, there are more options than ever before and fertility treatments are becoming increasingly advanced and reliable.

The latest breakthrough in fertility treatments is here in Australia, where a new technique in preimplantation genetic diagnosis (PGD) technology, called Advanced Embryo Selection has shown promising results in reducing a woman’s risk of miscarriage.

What is Advanced Embryo Selection (AES)?

Up to 70 per cent of embryos created are abnormal, meaning that they will not result in a healthy baby being born. AES is a form of preimplantation genetic diagnosis, which refers to genetic profiling of embryos prior to transfer into a patient. Advanced Embryo Selection is a new, more advanced PGD technique that allows scientists to select the best embryos for implantation in advance, decreasing the risk of miscarriage and increasing IVF pregnancy rates by up to 65%.

How does Advanced Embryo Selection Work?

Prior to implantation, all 24 chromosomes of a developing embryo are screened to determine whether or not there are any extra or missing chromosomes, which would inhibit a successful pregnancy.

By studying the individual chromosomes, scientists can identify whether or not a particular embryo would potentially result in a miscarriage, would not initiate a pregnancy at all or might result in birth defects such as Down Syndrome.

It takes approximately 36 hours to do the tests that will determine the potential success rate of an embryo. It is claimed to be the world’s fastest and most precise embryo selection test available.

Benefits of Advanced Embryo Selection

While typical non-selective lVF treatment is more than suitable for a lot of women, there are a range of benefits to using Advanced Embryo Selection as a preferred/additional technique.

The key benefit of AES is that chromosomes are accurately assessed prior to implantation, minimising the risk of miscarriage and failed pregnancies. It can mean less stress for the women involved and the process can be completed overnight so that embryos do not need freezing while results are pending.

Additionally, a patient’s IVF cycle can continue uninterrupted while the AES process is happening, largely due to the quick turn around time for results.

The tests on embryos are done from a single cell, which is biopsied on day three of embryo growth. This means that a patient will have more embryos available for testing.

Who is Advanced Embryo Selection for?

Advanced Embryo Selection is suitable for a lot of people with fertility problems, however it can be particularly beneficial for women who fit the following criteria:

Aged 38 years or over
A history of recurrent miscarriage
A history of failed IVF attempts
There has previously been an abnormally chromosomal pregnancy (e.g. Down Syndrome)

However, it is best to speak to your GP or fertility specialist about whether or not AES is suitable for your circumstances.

What is the Advanced Embryo Selection Process?

As mentioned above, the AES process involves a single-cell analysis from a three day old embryo. This single cell’s DNA is then multiplied thousands of times using comparative genomic hybridization technology, which is placed on a DNA chip.

This DNA is then assessed against normal male and female DNA. It is at this stage that scientists can detect whether or not an embryo is suitable for transfer. Only those that have a normal, healthy chromosomal profile will be chosen.

Further reading:

http://ivf.com.au/fertility-treatment/genetic-testing-pgd/advanced-embryo-selection

http://qfg.com.au/fertility-treatment/genetic-testing-pgd/advanced-embryo-selection

http://www.carefertility.com/genetics-programme-sc2/what-is-pgd-what-is-genetic-diagnosis-sj1/

Image credit: Flickr

PDF Resource Credit: Dr Michael Flynn

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