Category Archives: 2016

Detecting deadly foodborne pathogens on the spot

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Researchers from Saudi Arabia and Jordan have invented a cheap sensor that can detect foodborne pathogens within minutes and which can be used by anyone.

The sensor can detect, among other pathogens, Listeria monocytogenes, a notoriously harmful pathogen that has caused numerous infections worldwide and whose inspection and detection efforts exhaust billions of dollars every year, says a new study published in Biosensors & Bioelectronics.

The sensor itself is made of magnetic nanoparticles. It can detect minute traces or serial dilutions of Listeria in milk and meat, as the study demonstrates. “The sensor’s performance is superior in terms of its simplicity, cost and speed,” says researcher Mohammed Zourob, the study’s corresponding author.

Zourob adds that the sensor can be used by non-skilled personnel to check the food contamination; food manufacturers, stores, distributors and even laypersons can use it.

The biosensor changes color from black to yellow in less a minute time when it detects Listeria. Zourob’s team has also developed sensors that can detect other food pathogens such as Escherichia  coli, Salmonella, Shigella flexnerii and Staphylococcus aureus.

The Throes of AIDS

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Aids and drug testing equipment. Syringe. Paperwork. Graph. Blood. Coloured liquid. Sample. Medical research. Measurements. Charts. Cure. Treatment. Thermometer. Instruments.

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As scientists, press, leaders and activists meet at the 21st International AIDS conference in Durban, the Middle East and North Africa region remains embroiled in its own fight against HIV/AIDS.

The odds are stacked against this region, solidly among those groups where infections are increasing – an issue that the conference at Durban is expected to mount concerns about, among others. In addition to discussing the state of the epidemic worldwide, and in high-risk areas, the conference will address the fact that HIV/AIDS is plateauing or peaking in several countries, plus the level of jeopardy this entails.

In this region, 80% of people living with HIV/AIDS are not aware they’re carrying the virus, 85% of those in progressive stages of infection are not receiving treatments and deaths due to AIDS have increased 176%, according to reports from UNAIDS and WHO. There are not enough national strategic plans to tackle the problem and access to life-saving medications remains limited.

Stigma is partly to blame, according to Navid Madani, senior scientist in the Department of Cancer Immunology and Virology at Dana-Farber Cancer Institute and the Department of Global Health and Social Medicine at Harvard Medical School.

Globally, growing resistance to the antiretroviral drugs used against HIV is the most serious issue facing plans to end the endemic, according to the WHO’s opening statement to Durban’s conference this morning.

Finding preventive measures and a vaccine-antiviral combination that might bring us closer to a cure are underway. In fact only this week, a new study in Science provides insights into the workings of new HIV drugs and into how the virus becomes resistant. Scientists can use these to scrutinize structures insides irregular viruses like HIV to understand the molecular underpinnings of the virus in order to come up with new drug designs.

But finding new drugs is an expensive affair, as meanwhile funding for HIV has been dropping.

Back in the Middle East and North Africa, the extent of the HIV epidemic is undeniable, and governments – some reluctantly and others readily – are beginning to understand there’s a problem in need of curbing.

Just as pivotal to halting the spread is the culture of HIV-related practices, the shame surrounding the virus, the inequality cited by many in terms of medication access and the outdated fears about the prognosis for those infected. The burden falls on scientists, policymakers, healthcare workers and even at-risk communities to try and change the status quo.

Historic genetic ‘picture’ of Arabian camel revealed

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Camels blogpost

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An analysis of the ancient and modern DNA of the single-humped ‘Arabian’ camel or dromedary reveals how human societies have influenced the animal’s genetic diversity.

Long-distance and back-and-forth movements in ancient camel caravan routes are one way this has happened.

The camels have long been a source of food and transport for desert communities, and a vital resource in trade and agriculture in hot, arid regions. That’s why the scientists responsible for this study believe that in the context of climate change and advancing desert landscapes, scrutinizing dromedary’s biology, reproduction and adaptation to hostile terrain has acquired a new level of importance.

“The dromedary has out-performed all other domesticated mammals, including the donkey, in arid environments and continues to provide essential commodities to millions of people living in marginal agro-ecological areas,” says lead author Faisal Almathen from the Department of Veterinary Health and Animal Husbandry at King Faisal University.

“There is very little defined population structure in modern dromedaries. We believe this is a consequence of cross-continental back and forth movements along historic trading routes,” he adds. “Our results point to extensive gene flow which affects all regions except East Africa where dromedary populations have remained relatively isolated.”

For this study, the researchers collected and analysed genetic information from a sample of 1,083 living dromedaries from 21 countries across the world. The team also examined ancient DNA sequences from bone samples from early-domesticated dromedaries from 400-1870 AD and wild ones from 5,000-1,000 BC.

The international team of scientists was led by geneticists from The University of Nottingham, the University of Veterinary Medicine in Vienna and King Faisal University in Saudi Arabia. The research itself is published in the Proceedings of the National Academy of Sciences of USA.

The ancient refuge of southern Arabia

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It seems that southern Arabia has provided shelter to people, 20,000 years earlier, following an ice age that made much of the Earth uninhabitable, according to new evidence provided by University of Huddersfield researchers this week.

Once the Ice Age receded, the Red Sea plains of what we know now as southern Arabia in addition to the far side of the Bab el-Mandeb strait and the Horn of Africa were among glacial sanctuaries where people were able to cluster and survive.

This has been hypothesized before by scientists but never confirmed until this study.

It defies what was commonly thought of Arabia; that humans did not settle there in large numbers until the development of agriculture, roughly 10,000 years earlier.

Analyzing mitochondrial DNA for a lineage that’s common in Arabia and the horn of Africa, the researchers discovered that the lineage, named R0a, is more ancient than what was thought.

The ancient gene flow infiltrated the horn, well before the spread of agriculture into that region. It seeped into the rest of the Middle East (present day Iran, Pakistan and India) and other territories, like Europe through the movement of people and the development of trading networks.

The study mapping human dispersals, post the Ice Age, and deep ancestry was published in Scientific Reports. The DNA analyzed was extracted from living people, since to date this couldn’t be recovered from prehistoric remains. So the scientists had to rely on modern diversity to draw conclusions about the history of the DNA lineage.